abis interface

BTS-BSC Inter-operability (Abis Interface) A.S0003-Av2.0 (to be published as TIA/EIA-828-A)

3GPP2 A.S0003-A

Version 2.0

Date: July 2001

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BTS-BSC Inter-operability (Abis Interface) 9

(Post SDO Ballot, Pre-SDO Publication) 10

11 12 13 14 15 16 17 18 19 20 © 3GPP2 2001 21 22 3GPP2 and its Organizational Partners claim copyright in this document and individual Organizational Partners 23 may copyright and issue documents or standards publications in individual Organizational Partner's name 24 based on this document. Requests for reproduction of this document should be directed to the 3GPP2 25 Secretariat at [email protected]. Requests to reproduce individual Organizational Partner's documents 26 should be directed to that Organizational Partner. See www.3gpp2.org for more information. 27 28

A.S0003-Av2.0 BTS-BSC Inter-operability (Abis Interface) (to be published as TIA/EIA-828-A)

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Table of ContentsTable of ContentsTable of ContentsTable of Contents 1 1. Introduction............................................................................................................................................ 2 2 2. Objectives................................................................................................................................................ 2 3

2.1 Scope of the document ......................................................................................................................... 2 4 2.2 References ............................................................................................................................................ 2 5

2.2.1 Telecommunications Industry Association (TIA) / Electronics Industry Association (EIA)........... 3 6 2.2.2 Standards Committee T1................................................................................................................ 3 7 2.2.3 International Telecommunications Union - Telecommunications Sector (ITU-T) ......................... 3 8 2.2.4 Other ............................................................................................................................................. 3 9

3. Terminology ............................................................................................................................................ 4 10 3.1 Acronyms ............................................................................................................................................. 4 11 3.2 Others ................................................................................................................................................... 5 12

4. Network Reference Model and Interfaces............................................................................................ 6 13 4.1 Support of user traffic connections to a frame selector function .......................................................... 9 14 4.2 Support of paging channel messaging .................................................................................................. 9 15 4.3 Support of Access channel messaging................................................................................................ 10 16 4.4 Support of broadcast system information functions ........................................................................... 10 17 4.5 Layers 1 & 2 ....................................................................................................................................... 10 18

4.5.1 Physical Layer Specification (Layer 1) ....................................................................................... 10 19 4.5.2 Use of ATM (Layer 2) .................................................................................................................. 10 20 4.5.3 Field of Application..................................................................................................................... 10 21 4.5.4 ATM Layer................................................................................................................................... 11 22 4.5.5 ATM Adaptation Layer ................................................................................................................ 11 23 4.5.6 Network and Transport Protocols ............................................................................................... 11 24

5. Call Processing ..................................................................................................................................... 16 25 5.1 Mobile Originating Call ..................................................................................................................... 16 26

5.1.1 Abis-ACH Message Transfer ....................................................................................................... 16 27 5.1.2 Unused Section............................................................................................................................ 17 28 5.1.3 Abis-BTS Setup............................................................................................................................ 17 29 5.1.4 Abis-Connect ............................................................................................................................... 17 30 5.1.5 Abis-Connect Ack ........................................................................................................................ 17 31 5.1.6 Abis-BTS Setup Ack ..................................................................................................................... 18 32 5.1.7 Abis-IS-2000 FCH Forward........................................................................................................ 18 33 5.1.8 Abis-IS-2000 FCH Reverse ......................................................................................................... 19 34 5.1.9 Abis-PCH Msg Transfer .............................................................................................................. 19 35 5.1.10 Abis-PCH Msg Transfer Ack.................................................................................................... 20 36 5.1.11 Abis-Traffic Channel Status ..................................................................................................... 20 37 5.1.12 Successful Mobile Originating Call......................................................................................... 21 38

5.2 Mobile Terminated Call ...................................................................................................................... 25 39 5.2.1 Abis-PCH Message Transfer ....................................................................................................... 25 40 5.2.2 Abis-PCH Message Transfer Ack ................................................................................................ 25 41 5.2.3 Abis-BTS Setup............................................................................................................................ 25 42 5.2.4 Abis-Connect ............................................................................................................................... 25 43


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5.2.5 Abis-Connect Ack ........................................................................................................................ 25 1 5.2.6 Abis-BTS Setup Ack ..................................................................................................................... 26 2 5.2.7 Abis-IS-2000 FCH Forward........................................................................................................ 26 3 5.2.8 Abis-IS-2000 FCH Reverse ......................................................................................................... 26 4 5.2.9 Abis-ACH Message Transfer ....................................................................................................... 26 5 5.2.10 Unused section......................................................................................................................... 26 6 5.2.11 Abis-Traffic Channel Status ..................................................................................................... 26 7 5.2.12 Successful Mobile Terminated Call.......................................................................................... 27 8

5.3 Call Clearing....................................................................................................................................... 31 9 5.3.1 Call Clearing initiated by MS...................................................................................................... 31 10 5.3.2 Call Clearing initiated by BS/MSC ............................................................................................. 35 11 5.3.3 Call Clearing initiated by BTS .................................................................................................... 38 12 5.3.4 Call Clearing initiated by MS...................................................................................................... 41 13 5.3.5 Call Clearing initiated by BSC/MSC........................................................................................... 43 14 5.3.6 Call Clearing initiated by BTS .................................................................................................... 45 15

5.4 Handoff............................................................................................................................................... 47 16 5.4.1 Abis-BTS Interface Procedures and Messages ............................................................................ 47 17 5.4.2 Soft/Softer Handoff addition (Intra-BTS) .................................................................................... 54 18 5.4.3 Soft/Softer Handoff addition (Inter-BTS)..................................................................................... 56 19 5.4.4 Soft/Softer Handoff Removal (Inter-BTS) .................................................................................... 58 20 5.4.5 Hard Handoff (Inter-BTS) ........................................................................................................... 60 21

5.5 SMS Delivery ..................................................................................................................................... 63 22 5.5.1 SMS Delivery on the Paging channel .......................................................................................... 63 23 5.5.2 Call flow example for SMS Delivery on the Paging channel ...................................................... 65 24 5.5.3 SMS Delivery on the Access channel........................................................................................... 67 25 5.5.4 SMS Delivery on the Traffic channel to MS................................................................................. 70 26 5.5.5 SMS Delivery on the Traffic channel from MS ............................................................................ 71 27

5.6 Traffic Burst Operation....................................................................................................................... 72 28 5.6.1 Abis-Burst Request ...................................................................................................................... 72 29 5.6.2 Abis-Burst Response.................................................................................................................... 72 30 5.6.3 Abis-Burst Commit ...................................................................................................................... 73 31 5.6.4 High Speed Packet Data.............................................................................................................. 73 32 5.6.5 Initial Traffic Burst Example – Abis Connection Not Yet Established ......................................... 75 33 5.6.6 Subsequent Traffic Burst Example............................................................................................... 78 34

5.7 PACA Service ..................................................................................................................................... 80 35 5.7.1 PACA Updating ........................................................................................................................... 80 36 5.7.2 Call flow example for PACA Updating........................................................................................ 81 37

6. Abis Interface Message ........................................................................................................................ 82 38 6.1 Abis Interface Message Formats ........................................................................................................ 82 39

6.1.1 Message Body, Coding, and Ordering of Elements ..................................................................... 82 40 6.1.2 Message Processing Guidelines .................................................................................................. 84 41 6.1.3 Message Definition Guidelines.................................................................................................... 85 42

6.2 Abis interface messages...................................................................................................................... 86 43


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6.2.1 Abis-ACH Msg Transfer .............................................................................................................. 86 1 6.2.2 UNUSED SECTION.................................................................................................................... 89 2 6.2.3 Abis-PCH Msg Transfer .............................................................................................................. 89 3 6.2.4 Abis-PCH Msg Transfer Ack ....................................................................................................... 92 4 6.2.5 Abis-BTS Setup............................................................................................................................ 94 5 6.2.6 Abis-BTS Setup Ack ................................................................................................................... 101 6 6.2.7 Abis-BTS Release ...................................................................................................................... 105 7 6.2.8 Abis-BTS Release Ack................................................................................................................ 107 8 6.2.9 Abis-Burst Request .................................................................................................................... 108 9 6.2.10 Abis-Burst Response .............................................................................................................. 113 10 6.2.11 Abis-Burst Commit................................................................................................................. 117 11 6.2.12 Abis-Connect.......................................................................................................................... 122 12 6.2.13 Abis-Connect Ack................................................................................................................... 127 13 6.2.14 Abis-Remove .......................................................................................................................... 127 14 6.2.15 Abis-Remove Ack ................................................................................................................... 127 15 6.2.16 Abis-IS-2000 FCH Fwd ......................................................................................................... 127 16 6.2.17 Abis-IS-2000 FCH Rvs........................................................................................................... 127 17 6.2.18 Abis-Traffic Channel Status ................................................................................................... 127 18 6.2.19 Abis-BTS Release Request ..................................................................................................... 127 19 6.2.20 Abis-IS-2000 SCH Fwd.......................................................................................................... 129 20 6.2.21 Abis-IS-2000 SCH Rvs ........................................................................................................... 129 21 6.2.22 Abis-IS-2000 DCCH Fwd ...................................................................................................... 129 22 6.2.23 Abis-IS-2000 DCCH Rvs ....................................................................................................... 129 23 6.2.24 Abis-PACA Update................................................................................................................. 129 24

7. Information Element Definitions ...................................................................................................... 131 25 7.1 Information Element Identifiers ....................................................................................................... 131 26 7.2 Message Type ................................................................................................................................... 133 27 7.3 Correlation ID................................................................................................................................... 134 28 7.4 Mobile Identity ................................................................................................................................. 134 29 7.5 Cell Identifier ................................................................................................................................... 134 30 7.6 Air Interface Message....................................................................................................................... 134 31 7.7 UNUSED SECTION........................................................................................................................ 135 32 7.8 Layer 2 Ack Request/Results............................................................................................................ 135 33 7.9 Cause ................................................................................................................................................ 135 34 7.10 Call Connection Reference ........................................................................................................... 135 35 7.11 Band Class .................................................................................................................................... 135 36 7.12 Privacy Info................................................................................................................................... 135 37 7.13 Cell Identifier List......................................................................................................................... 135 38 7.14 SDU ID ......................................................................................................................................... 135 39 7.15 Physical Channel Info ................................................................................................................... 135 40 7.16 Cell Information Record ............................................................................................................... 136 41 7.17 Service Option .............................................................................................................................. 136 42 7.18 PACA Timestamp.......................................................................................................................... 136 43


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7.19 Quality of Service Parameters....................................................................................................... 136 1 7.20 Abis Connect Information............................................................................................................. 136 2 7.21 Abis Originating ID ...................................................................................................................... 136 3 7.22 Abis Destination ID ...................................................................................................................... 137 4 7.23 Downlink Radio Environment ...................................................................................................... 137 5 7.24 CDMA Serving One Way Delay ................................................................................................... 137 6 7.25 Forward Burst Radio Info ............................................................................................................. 138 7 7.26 Reverse Burst Radio Info.............................................................................................................. 138 8 7.27 IS-2000 Forward Power Control Mode......................................................................................... 138 9 7.28 IS-2000 FPC Gain Ratio Info ....................................................................................................... 138 10 7.29 BTS L2 Termination ..................................................................................................................... 138 11 7.30 CDMA Target One Way Delay ..................................................................................................... 139 12 7.31 Walsh Code Assignment Reqest ................................................................................................... 139 13 7.32 PACA Order .................................................................................................................................. 139 14 7.33 Authentication Challenge Parameter (RAND).............................................................................. 140 15 7.34 Abis Ack Notify ............................................................................................................................ 141 16

8. Timer Definitions ............................................................................................................................... 142 17 8.1 Tconnb :Timer for Abis-Connect message ....................................................................................... 142 18 8.2 Tsetupb : Timer for Abis-BTS Setup message.................................................................................. 142 19 8.3 Tchanstatb : Timer for Abis-Traffic Channel Status message........................................................... 142 20 8.4 Tdisconb : Timer for Abis-Remove Ack message ............................................................................ 143 21 8.5 Tdrptgtb : Timer for Abis-BTS Release Ack message...................................................................... 143 22 8.6 Tbstreqb : Timer for Abis-Burst Response message......................................................................... 143 23 8.7 Tbstcomb : Timer for Abis-BTS Release Ack message.................................................................... 143 24 8.8 Trelreqb : Timer for Abis-BTS Release message.............................................................................. 143 25

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Table of Figures 1 FIGURE 4-1 REFERENCE MODEL .........................................................................................................6 2 FIGURE 4-2 RELATIONSHIP BETWEEN AIR INTERFACE AND ABIS INTERFACE (INTRA-BS MODEL) ......8 3 FIGURE 4.5.6.4.1-1 DELIMITING MESSAGES IN AN ABIS APPLICATION TCP BYTE STREAM..............14 4 FIGURE 5.1.12-1 MOBILE ORIGINATING CALL...................................................................................21 5 FIGURE 5.2.12-1 MOBILE TERMINATED CALL ...................................................................................27 6 FIGURE 5.3.4-1 CALL CLEARING INITIATED BY MS ...........................................................................41 7 FIGURE 5.3.5-1 CALL CLEARING INITIATED BY BSC/MSC ................................................................43 8 FIGURE 5.3.6-1 CALL CLEARING INITIATED BY BTS..........................................................................45 9 FIGURE 5.4.2-1 SOFT/SOFTER HANDOFF ADDITION (INTRA-BTS) .....................................................54 10 FIGURE 5.4.3-1 SOFT/SOFTER HANDOFF ADDITION (INTER-BTS) .....................................................56 11 FIGURE 5.4.4-1 SOFT/SOFTER HANDOFF REMOVAL (INTER-BTS) .....................................................58 12 FIGURE 5.4.5-1 HARD HANDOFF (INTER-BTS)..................................................................................60 13 FIGURE 5.5.2-1 SMS DELIVERY ON THE PAGING CHANNEL ..............................................................65 14 FIGURE 5.5.3.5-1 SMS DELIVERY ON THE ACCESS CHANNEL ...........................................................69 15 FIGURE 5.5.4-1 SMS DELIVERY ON THE TRAFFIC CHANNEL TO MS .................................................70 16 FIGURE 5.5.5-1 SMS DELIVERY ON THE TRAFFIC CHANNEL FROM MS.............................................71 17 FIGURE 5.6.5-1 INITIAL TRAFFIC BURST EXAMPLE...........................................................................75 18 FIGURE 5.6.6-1 SUBSEQUENT TRAFFIC BURST EXAMPLE .................................................................78 19 FIGURE 5.7.2-1 PACA UPDATING PROCEDURE..................................................................................81 20 21

22 Table of Tables 23

TABLE 4-1 LAYER 2 TERMINATION TYPE ..............................................................................................6 24 TABLE 4-2 ABIS INTERFACE DESCRIPTION............................................................................................9 25 TABLE 6.1.1-1 ELEMENT FLOW DIRECTION INDICATION...............................................................82 26 TABLE 7.1-1 ABIS INFORMATION ELEMENT IDENTIFIERS SORTED BY IDENTIFIER VALUE...............131 27 TABLE 7.2-1 ABIS MESSAGE TYPE VALUES......................................................................................133 28 TABLE 8-1 TIMER VALUES AND RANGE ............................................................................................142 29 30

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1. Introduction 1

This document is the specification for the Abis interface (between the Base Transceiver 2 System (BTS) and Base Station Controller (BSC) for IS-2000 system. The signaling 3 flows and these signals are described. 4

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2. Objectives 6

The Abis interface specification provides an open and inter-operable system. 7

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2.1 Scope of the document 9

This specification defines the interface between BTS and BSC within the BS. The 10 interface between BSs is specified in the TIA/EIA/IS-2001. 11

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Following features are not specified in this version of the specification. They are for 13 further study. 14 Operations, Administration, Maintenance, and Provisioning (OAM&P)*1 15

Abis Overload control 16

SMS-Broadcast 17

Inter BSC hard/soft handoff *2 18

Flood paging 19

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*1 It is recommended that any OAM&P related information be aligned with the 21 TIA/EIA-828, Abis interface. . 22

*2 Inter BSC (BS) hard/soft handoff is supported in the TIA/EIA/IS-2001. 23

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The functions supported in TIA/EIA/IS-2001 shall be supported implicitly for the Abis 25 interface and shall not modify the information transmitted on the radio channels. 26

The conditions for supporting Abis Interface features are equivalent to TIA/EIA/IS-2001. 27

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2.2 References 29

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2.2.1 Telecommunications Industry Association (TIA) / Electronics Industry 1 Association (EIA) 2

TIA/EIA/IS-2001; Inter-operability Specification (IOS) for CDMA 2000 Access Network 3 Interfaces (also referenced as 3GPP2 TSG-A’s A.S0001); December, 2000. 4

TIA/EIA/IS-95B; Mobile Station - Base Station Compatibility Standard for Dual-Mode 5 Wideband Spread Spectrum Cellular Systems; March, 1999 6

2.2.2 Standards Committee T1 7

ANSI T1.627 - 1993, B-ISDN - ATM Layer Functionality and Specification, 1993. 8

2.2.3 International Telecommunications Union - Telecommunications Sector 9 (ITU-T) 10

ITU-T Recommendation I.363.2, B-ISDN ATM Adaptation layer specification: Type 2 11 AAL; September, 1997. 12

ITU-T Recommendation I.363.5, B-ISDN ATM Adaptation Layer specification: Type 5 13 AAL; August, 1996. 14

ITU-T Recommendation I.366.1; Segmentation and Reassembly Service Specific Con-15 vergence Sublayer for the AAL type 2; June, 1998. 16

ITU-T Recommendation Q.2931, Broadband-Integrated Services Digital Network 17 (B-ISDN) Digital Subscriber Signalling No. 2 (DSS2) User-Network Interface Layer 3 18 Specification for Basic Call/Connection Control, 1995. 19

2.2.4 Other 20

Internet Engineering Task Force, RFC 791 - Internet Protocol (IP), 1981. 21

Internet Engineering Task Force, RFC 793 - Transmission Control Protocol (TCP), 1981. 22

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3. Terminology 1

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3.1 Acronyms 3

The following is a list of acronyms that are used in this specification text. 4 5 AAL2 ATM Adaptation Layer type 2 6 AAL5 ATM Adaptation Layer type 5 7 ADDS Application Data Delivery Service 8 ANSI American National Standards Institute 9 ARFCN Absolute Radio Frequency Channel Number 10 ATM Asynchromous Transfer Mode 11 BSC Base Station Controller 12 BSMAP Base Station Management Application Part 13 BTS Base Transceiver System 14 CC Conference Calling 15 CCITT International Telegraph and Telephone Consultative Committee (See ITU) 16 CDMA Code Division Multiple Access 17 CID Circuit IDentifier (used with reference to AAL2) 18 CM Connection Management 19 cUDP compressed IP/UDP 20 FCH Fundamental Channel 21 IETF Internet Engineering Task Force 22 IMSI International Mobile Subscriber Identity 23 IOS Interoperability Specification 24 IP Internet Protocol 25 ISDN Integrated Services Digital Network 26 ISLP Intersystem Link Protocol 27 ITU International Telecommunications Union 28 kb kilo bits 29 LAC Location Area Code 30 LSB Least Significant Bit 31 MAC Medium Access Control 32 MIN Mobile Identification Number 33 MS Mobile Station 34 MSB Most Significant Bit 35 MSC Mobile Switching Center 36 OAM&P Operations, Administration, Maintenance, and Provisioning 37 OTD Orthogonal Transmit Diversity 38 PACA Priority Access and Channel Assignment 39


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PATE Packet Arrival Time Error 1 PCF Packet Control Function 2 PCM Pulse Code Modulation 3 PN Pilot Number 4 PPP Point to Point Protocol 5 PSPDN Packet Switched Public Data Network 6 PSTN Public Switched Telephone Network 7 QoS Quality of Service 8 RAND Random Variable 9 RFC Request for Comment 10 RLP Radio Link Protocol 11 SCH Supplemental Channel 12 SCM Service Connect Message 13 SCTP Stream Control Transmission Protocol 14 SDU Selection/Distribution Unit function 15 SMS Short Message Service 16 SMS-MO SMS Mobile Originated 17 SMS-MT SMS Mobile Terminated 18 SSCS Service Specific Convergence Sublayer 19 SSD Shared Secret Data 20 SSSAR Service Specific Segmentation and Reassembly 21 TCP Transmission Control Protocol 22 UDP User Datagram Protocol 23

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3.2 Others 25

1) In this document the term “cell” is used to refer to a sector with in a cell. 26 2) The messages indicated with solid lines flow over the Abis interface and the messages 27

indicated with dashed lines flow over interfaces other than the Abis interface. 28


4. Network Reference Model and Interfaces 1

Figure 4-1 shows the network reference model that is referred to in this specification. 2 3

4 5 6 7 8 9 10 11 12 13 14 15 a) Abis interface 16 b) A Selection Dis17 c) A channel elem18 19

Notes: The h20 The 21

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24 There are 2 architecture for the25 4-1. 26 27

L r-csch(*1) L3 L3

AuthenticatioARQ

AddressingUtility

LAC

SAR

L2

MAC MAC L1 L1

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(*1) r-csch (reverse common signal29 This logical channel is appl30 In r-csch, LAC sub-layer is 31

Abis Signaling

c

Abis Signaling

Abis Traffic

BTS

B S

Abis Interface

BSC SDU Function

Abis Traffi

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= Abis signaling + Abis traffic tribution Unit (SDU) function is located in the BSC ent is located in the BTS

andoff procedure between BTSs within a BSC is defined in this document. handoff procedure between the BSs has been defined in TIA/EIA/IS-2001.

Figure 4-1 Reference Model

L2 terminations were considered. They are shown in the following Table

f-csch(*2) Type A Type B L3

n BSC

ARQ Addressing

Utility SAR MAC

BSC

L1

BTS

BTS

Table 4-1 Layer 2 termination type ing logical channel) ied for the case that MS sends message on the ACH and BTS replies on the PCH. composed by Authentication sub-layer, ARQ sub-layer, Addressing sub-layer, Utility

BTS CH element CH element


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sub-layer and SAR sub-layer. 1 (*2) f-csch (forward common signaling logical channel) 2 This logical channel is applied for the case that BTS sends message on the PCH and MS replies on the ACH. 3 In f-csch, LAC sub-layer is composed ARQ sub-layer, Addressing sub-layer, Utility sub-layer and SAR sub-layer. 4 In this specification type A is introduced as architecture for initial phase. However we are also introducing 5 type B for the next release. 6 7 In this release of the Abis specification L2 termination is mandatory to be supported by the BTS. To allow 8 for a migration to new architectures, a mechanism is provided on the Abis interface whereby the BTS can 9 specify if L2 termination function will be supported. If the BTS indicates that it does not support L2 10 termination, then the BSC shall support L2 termination. In this release of the Abis specification the BTS shall 11 specify to the BSC that it terminates L2 termination. 12 13 14

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Figure 4-2 shows the relationship between logical air interface channels and Abis interface signal 1

2 Note:This figure is informative. In this figure, some signals defined in the air interface are omitted for 3 clarity. 4

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Figure 4-2 Relationship between Air interface and Abis interface (Intra-BS Model) 6

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BSCBTS

Abis Signaling

OAM Signaling

MS

FCH (f/r-dsch, f/r-dtch)

SCH (f/r-dtch)

DCCH (f/r-dsch, f/r-dtch)

ACH (r-csch)PCH (f-csch)

Abis Interface

DCCH (Abis-IS-2000 DCCH Fwd/Rvs)

FCH (Abis-IS-2000 FCH Fwd/Rvs)

SCH (Abis-IS-2000 SCH Fwd/Rvs)

PCH (Abis-PCH Msg Transfer)ACH (Abis-ACH Msg Transfer)

Air Interface

(FFS)

BS

Abis Signaling

Abis traffic


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Table 4-2 summaries the details of the Abis interface 1 2

Table 4-2 Abis interface description 3

Abis function Transaction Abis Message (A7/A3 message related to Abis)

Abis connection establish (BSC invoke)

- call setup - Handoff

- Abis-BTS Setup - Abis-BTS Setup Ack - Abis-Connect - Abis-Connect Ack

(A7-HO Req.) (A7-HO Req. Ack) (A3-Connect) (A3-Connect Ack)

Abis connection release (BSC invoke)

- call release - Handoff

- Abis-BTS Release - Abis-BTS Release Ack - Abis-Remove - Abis-Remove Ack

(A7-Drop) (A7-Drop Ack) (A3-Remove) (A3-Remove Ack)

Abis connection release (BTS invoke)

- Abis-BTS Release Request - Abis-BTS Release - Abis-BTS Release Ack - Abis-Remove - Abis-Remove Ack

(A7-Tgt rm. req.) (A7-Drop) (A7-Drop Ack) (A3-Remove) (A3-Remove Ack)

PCH transfer - Abis-PCH Msg Transfer - Abis-PCH Msg Transfer Ack

(A7-PCH ...) (A7-PCH ... Ack)

ACH transfer - Abis-ACH Msg Transfer (A7-ACH ...) SCH transfer and establish

- SCH setup - Abis-Burst Request - Abis-Burst Response -Abis-Burst Commit

(A7-Burst Req.) (A7-Burst Rsp.) (A7-Burst Commit)

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4.1 Support of user traffic connections to a frame selector function 5

In a CDMA system, the user traffic (voice, data, etc.) of a Mobile Station (MS) may be 6 connected to the network using one or more connections from MS to BTS(s). If multiple 7 connections are used for a single flow of user information, the user traffic connection is 8 said to be in soft handoff. The first step within the network is to carry these multiple 9 connections back to a single point from which a selection is made of the “best” frame 10 received over the radio connections. This implies a connection from each involved BTS 11 back to a central point where frame selection occurs. This central point is referred to as 12 the “SDU function.” 13 14

4.2 Support of paging channel messaging 15

When an MS is to be sent a message on a paging channel, the BSC typically formats the 16 majority of the message and forwards it to the BTS along with various parameters 17 including the destined cell identifier. The ability to forward such a paging message from 18 the BSC to the BTS is part of the functionality of the Abis interface. 19

An additional requirement of a CDMA system is that such a message may also need to be 20 forwarded between BSCs to be transmitted on a BTS belonging to a BSC other than the 21


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BSC that originally created the message. This requirement comes through support for 1 access handoff and other such IS-95 and IS-2000 features. The BSC to BSC signaling 2 interface to support such forwarding has been defined in the TIA/EIA/IS-2001. 3

4.3 Support of Access channel messaging 4

When an MS sends a message on an access channel, the BTS will forward that message 5 to the BSC along with various parameters including the identity of the cell and sector on 6 which the message was received, etc. The ability to forward such an access message from 7 BTS to the BSC is part of the functionality of the Abis interface. 8

An additional requirement of a CDMA system is that such a message may also need to be 9 forwarded between BSCs (i.e., to a BSC other than the one that owns the BTS that 10 originally received the message). This requirement comes through support for access 11 handoff and other such IS-95 and IS-2000 features. The BSC to BSC signaling interface 12 to support such forwarding has been defined in the TIA/EIA/IS-2001. 13

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4.4 Support of broadcast system information functions 15

In a IS-95 or a IS-2000 system, each BTS broadcasts various pieces of system 16 information that the MS captures and uses during its interactions with the network. Much 17 of that system information may be administrated through OAM&P functions. A small 18 amount of such system information may be placed in BTS and OAM&P control of a BTS 19 for the same purposes. 20

4.5 Layers 1 & 2 21

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4.5.1 Physical Layer Specification (Layer 1) 23

The physical layer specification is flexible to deploy the various new technologies. 24 Vendors shall have flexibility in providing the latest technology. And operators shall 25 have flexibility in choosing from various options, including T1, E1, 10/100 base T, OC3, 26 OC12, etc. 27 28

4.5.2 Use of ATM (Layer 2) 29

Asynchronous Transfer Mode (ATM) is a suite of protocols that allow fast, efficient 30 delivery of user traffic in a packet environment. ATM, for the purposes of this standard, 31 consists of two main layers: the ATM Layer that uses the physical layer, and the ATM 32 Adaptation Layer that adapts the basic ATM layer to specific usage. 33

4.5.3 Field of Application 34

Asynchronous Transfer Mode (ATM) is used to transport both signaling and user traffic 35 (voice/data). 36


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4.5.4 ATM Layer 1

The ATM Layer uses a basic 53-octet cell consisting of a 5-octet header and 48-octet 2 payload. This standard uses the ATM Layer as specified in ANSI T1.627-1993 3 Telecommunications Broadband ISDN - ATM Layer Functionality and Specification 4 without modification. 5

For this specification only ATM permanent virtual circuits (PVC’s) shall be required for 6 the Abis interface. These virtual circuits shall be configured through administrative 7 procedures and no special signaling interface procedures, e.g., ATM UNI (Q.2931), shall 8 be required. 9

4.5.5 ATM Adaptation Layer 10

To make use of the basic cell transfer capability of the ATM Transport Layer in specific 11 uses, various ATM Adaptation Layers (AALs) have been defined. 12

Within this standard, two AALs are used: 13

AAL51 - for the transfer of signaling, and 14

AAL22 - for the transfer of user traffic (voice/data) on Abis traffic sub-channels. 15

Both AAL5 and AAL2 are used without modification in this standard. The Service 16 Specific Segmentation and Re-assembly (SSSAR) sub-layer for AAL2, as specified in 17 ITU-T I.366.1, is used for segmentation and re-assembly of AAL2 SDUs. 18

In this version of this standard, the functionality of other sub-layers of AAL2 is not 19 supported. Specifically, Service Specific Transmission Error Detection (SSTED) and 20 Service Specific Assured Data Transfer (SSADT) are not included. 21

4.5.6 Network and Transport Protocols 22 23

4.5.6.1 Signaling Connection Transport Protocol Options 24

Signaling over the Abis interface requires a reliable transport protocol and appropriate 25 addressing and routing mechanisms to deliver messages from source to destination. The 26 Abis signaling application is independent of the underlying transport, which is left to the 27 discretion of operators and manufacturers. The signaling protocol stack options available 28 to operators and manufacturers for the Abis interface include: 29

30 Abis Interface (signaling connection): 31

32 IOS Application

TCP IOS Application

TCP IOS Application

UDP IOS Application

SCTP

1 AAL5 is described in ITU-T I.363.5, B-ISDN ATM Adaptation Layer Specification: Type 5 AAL, August 1996.

2 AAL2 is described in ITU-T Recommendation I.363.2, B-ISDN ATM Adaptation Layer Type 2 Specification, September 1997.


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IP AAL5

ATM

Phys. Lyr.

IP Link Layer

Phys. Lyr.

(Note 1)

IP Link Layer

Phys. Lyr.

(Note 1)

IP Link Layer

Phys. Lyr.

(Note 1) 1

It is mandatory for operators and manufacturers to support ATM based link layer for 2 signaling over the Abis interface. The other signaling connection may support any of 3 the protocol stacks above and is left to the discretion of operators and vendors. 4

UDP may be used and limited to those cases when reliable delivery is not required : e.g., 5 case when BSC sends general page message. 6

(Note 1) These protocol stacks shown in the table are examples. 7 8

4.5.6.2 User Traffic Connection Transport Protocol Options 9

The protocol stack options for transport of user traffic that are available to operators and 10 manufacturers include: 11

12 Abis Interface (user traffic sub-channel): 13 14

Abis Traffic

SSSAR AAL2

ATM

Phys. Layer

Abis Traffic UDP

IP Link Layer

Phys. Layer

(Note 1)

Abis Traffic cUDP SSCS AAL2

ATM

Phys. Layer (Note 1)

Abis Traffic cUDP

PPPmux Link Layer

Phys. Layer

(Note 1)

15

It is mandatory for operators and manufacturers to support ATM based transport for user 16 traffic over the Abis interface. The other signaling connection may support any of the 17 protocol stacks above and is left to the discretion of operators and vendors. 18

(Note 1) These protocol stacks shown in the table are examples. 19 20

4.5.6.3 TCP Transport Protocol Usage 21

The standard TCP, as described in RFC 793, shall be used for establishing, using, and 22 clearing TCP connections. 23

4.5.6.4 General Use of TCP 24

TCP connections for signaling may be set up on a per-call basis or signaling messages for 25 multiple calls may be multiplexed on a single TCP connection. 26

The TCP provides a reliable byte stream transfer. Therefore, a means needs to be 27 provided for two application entities to delimit the messages sent between them. The 28 technique for such delimitation is as follows. 29


13

4.5.6.4.1 Message Delimiting in TCP 1

TCP provides a reliable byte stream between two application entities. Because the 2 protocol in this standard uses messages to communicate, these messages shall be 3 delimited in the TCP byte stream. Such delimitation shall be done by means of a 4 two-byte flag field and a two-byte length field inserted at the beginning of each message 5 sent over a TCP connection. The flag field shall contain the hex value “F634”. The 6 purpose of the flag field is to facilitate verification of message boundaries and fast 7 reestablishment of synchronization if synchronization of message boundaries is lost. 8 See Figure 4.5.6.4.1-1: 9

10


14

1 7 6 5 4 3 2 1 0

Flag 1 1 1 1 0 1 1 0

Flag 0 0 1 1 0 1 0 0

Length (MSB)

Length (LSB)

First Octet of Abis Application Message

Second Octet of Abis Application Message

Msg Third Octet of Abis Application Message

. . .

Last Octet of Abis Application Message

Flag 1 1 1 1 0 1 1 0

Flag 0 0 1 1 0 1 0 0

Length (MSB)

Length (LSB) First Octet of Abis Application Message



. . .

Last Octet of Abis Application Message

Flag 1 1 1 1 0 1 1 0

Flag 0 0 1 1 0 1 0 0

Length (MSB)

Length (LSB) First Octet of Abis Application Message



. . .

Figure 4.5.6.4.1-1 Delimiting Messages in an Abis Application TCP Byte Stream 2

4.5.6.4.2 TCP Connection Establishment 3

A new TCP connection is established when a signaling message related to a call has to be 4 exchanged over an interface, and no such connection exists over the particular interface. 5 Normal TCP connection establishment procedures are used. 6


15

4.5.6.4.3 TCP Connection Release 1

An existing TCP connection over an interface is released when there are no more 2 signaling messages to be exchanged over the interface. Normal TCP connection release 3 procedures are used. 4

4.5.6.4.4 TCP Port Usage 5

The following TCP port values are reserved for signaling across Abis interfaces: 6

Abis: 5604 -- This is the well-known TCP port at a BS used for Abis signaling 7 interconnection between BTSs and a BSC. 8

9

4.5.6.5 Use of TCP for the Abis Interface 10

The standard "Transport Control Protocol (TCP)", as described in RFC 793 and shown in 11 TIA/EIA/IS-2001 section 5.4.1. 12

4.5.6.6 IP Network Protocol Usage 13

The standard IP protocol, as defined in RFC 791 (see TIA/EIA/IS-2001 section 1.5.4), 14 shall be used for routing Internet Protocol packets. 15

16


16

5. Call Processing 1

2

5.1 Mobile Originating Call 3

The following subsections describe the procedure for establishing a call through a mobile 4 originating action. 5

Mobile originating call setup involves exchange of the following BSC-BTS messages: 6

Abis-ACH Msg Transfer 7

8

Abis-BTS Setup 9

Abis-Connect 10

Abis-Connect Ack 11

Abis-BTS Setup Ack 12

Abis-IS-2000 FCH Fwd 13

Abis-IS-2000 FCH Rvs 14

Abis-PCH Msg Transfer 15

Abis-PCH Msg Transfer Ack 16

Abis-Traffic Channel Status 17

18

5.1.1 Abis-ACH Message Transfer 19

The Abis-Access Channel(ACH) Message Transfer is sent by the BTS to the BSC to 20 notify the BSC of the reception of an access channel message. 21

5.1.1.1 Successful Operation 22

When the BTS receives an access channel message, it shall encapsulate that message in 23 the Abis-ACH Msg Transfer, forward it to the BSC. The BTS may be responsible for 24 sending the Data Burst message for such forwarded access channel message. 25

26

Please refer to section 6.2.1, “Abis-ACH Msg Transfer,” for the format and content of 27 this message. 28

5.1.1.2 Failure Operation 29

None. 30

31


17

5.1.2 Unused Section 1

2

5.1.3 Abis-BTS Setup 3

The Abis-BTS Setup message is used by the BSC to request that the BTS allocate 4 resources in one or more cells for support of a call association. 5


When the BSC decides that one or more cells at the BTS are needed to support one or 7 more physical channel connections for a call, the BSC sends an Abis-BTS Setup message 8 to the BTS to indicate the resources required. The BSC then starts timer Tsetupb. 9

Please refer to section 6.2.5, “Abis-BTS Setup,” for the format and content of this 10 message. 11


If timer Tsetupb expires, the BSC may choose to resend the Abis-BTS Setup message. 13

14

5.1.4 Abis-Connect 15

The Abis-Connect message is sent from the BTS to the BSC to initiate to one or more 16 Abis traffic connection. The Abis-Connect Ack message is expected in response. 17


Upon receiving the Abis Signaling Address information, the BTS begins the process of 19 establishing the Abis signaling connection with the BSC. The Abis Signaling Address is 20 used by the BTS to allocate a logical circuit to be used for Abis signaling. The SDU ID 21 identifies the particular instance of the SDU function. 22

Following the establishment of the Abis signaling link, the Abis-Connect message is sent 23 from the BTS to the BSC. The BTS expects an Abis-Connect Ack message indicating the 24 result of processing the Abis-Connect message and starts timer Tconnb. When the Abis 25 traffic connection(s) is established, traffic packets are exchanged to verify that the two 26 entities can communicate via the Abis traffic connection(s). 27

Please refer to section 6.2.12, “Abis-Connect,” for the format and content of this 28 message. 29


If timer Tconnb expires, the BTS may choose to resend the Abis-Connect message. 31

32

5.1.5 Abis-Connect Ack 33

The Abis-Connect Ack message is sent from the BSC to the BTS to indicate the result of 34 processing the Abis-Connect message. 35


18


After processing the Abis-Connect message from the BTS, the BSC will indicate 2 success/failure to the BTS by sending an Abis-Connect Ack message. 3

If the Abis-Connect Ack message indicates that Abis-Traffic Channel Status message are 4 to be sent, then the BSC starts timer Tchanstatb to await Abis-Traffic Channel Status 5 message(s) for all new cells on each Abis connection. One instance of this timer is started 6 for each Abis connection to which one or more cells are being added. 7

Please refer to section 6.2.13, “Abis-Connect Ack,” for the format and content of this 8 message. 9


If an instance of timer Tchanstatb expires, the BSC may assume that a failure has 11 occurred at the BTS during activation of the transmitter(s)/receiver(s) and delete the 12 unreported cells from the active set attached to the Abis connection. The BSC may then 13 send an Abis-BTS Release message to the BTS to cleanly remove those cells from the 14 Abis connection. 15

16

5.1.6 Abis-BTS Setup Ack 17

The Abis-BTS Setup Ack message is used by the BTS to respond to a request that it 18 allocates resources in one or more cells for support of one or more physical channel 19 connections for a call association. 20


When the BTS receives an Abis-BTS Setup message, it determines what internal 22 resources are needed to support the requested physical channels for the call association. 23 Once those resources are allocated and the Abis-Connect Ack message(s) has been 24 received, the BTS responds by sending an Abis-BTS Setup Ack message to the BSC. 25

Please refer to section 6.2.6, “Abis-BTS Setup Ack,” for the format and content of this 26 message. 27


None. 29

30

5.1.7 Abis-IS-2000 FCH Forward 31

This message is sent from the BSC to the BTS on the Abis traffic subchannel connection 32 of type “IS-2000 FCH” (TIA/EIA/IS-2000 Fundamental Channel). It contains the 33 Forward air-frame for the served MS along with control information for the BTS. 34


This message is sent from the BSC to the BTS on Abis traffic subchannel connections of 36 type “FCH” (Fundamental Channel). FCH messages are sent once every 20ms. 37


19

Please refer to section 6.2.16, “Abis-IS-2000 FCH Fwd,” for the format and content of 1 this message. 2


None. 4

5

5.1.8 Abis-IS-2000 FCH Reverse 6

This message is sent from the BTS to the BSC on Abis traffic subchannel connections of 7 type “IS-2000 FCH” (TIA/EIA/IS-2000 Fundamental Channel). It contains the decoded 8 Reverse Traffic Channel frame received from the served MS along with control 9 information. 10


This message is sent to the BSC on the Abis traffic subchannel connections of type 12 “IS-2000 FCH” (TIA/EIA/IS-200 Fundamental Channel) following the decoding of the 13 Reverse Traffic Channel frame. IS-2000 frames are sent once every 20ms. 14

Please refer to section 6.2.17, “Abis-IS-2000 FCH Rvs,” for the format and content of 15 this message. 16


None. 18

19

5.1.9 Abis-PCH Msg Transfer 20

The Abis-Paging Channel (PCH) Msg Transfer is sent by the BSC to request that a 21 particular message is sent on the specified paging channel(s). 22

23


When the BSC wishes to send a message to the mobile station on the paging channel(s) of 25 the BTS, it encapsulates that message in an Abis-(PCH) Msg Transfer and sends it to the 26 BTS. 27

A Layer 2 acknowledgment indication can be requested. If such an acknowledgment is 28 received from the MS, an Abis-Paging Channel Message Transfer ACK message is used 29 to convey that information back to the BSC 30

Please refer to section 6.2.3, “Abis-PCH Msg Transfer” for the format and content of this 31 message. 32


None. 34

35


20

5.1.10 Abis-PCH Msg Transfer Ack 1

The Abis-PCH Msg Transfer Ack is used to respond to a request for a Layer 2 2 acknowledgment included in an Abis-PCH Msg Transfer. 3


When the BTS receives the Abis-PCH Msg Transfer including Abis Ack Notify IE, the 5 BTS sends the Abis-PCH Msg Transfer Ack upon receipt of the Layer 2 6 acknowledgment. 7

Please refer to section 6.2.4, “Abis-PCH Msg Transfer Ack” for the format and content of 8 this message. 9


None. 11

12

5.1.11 Abis-Traffic Channel Status 13

The Abis-Traffic Channel Status message is used by the BTS to notify the BSC that radio 14 transmission on the forward link has begun for the indicated cells, and that the 15 corresponding receivers have been activated. This message is sent when the 16 Abis-Connect Ack message indicates that it is requested. 17


When the BTS needs to notify the BSC of a status change relative to a specific set of cells 19 on one Abis connection, it sends an Abis-Traffic Channel Status message. 20

This message can be used to note that the indicated set of cells has begun radio 21 transmission on the forward link and that the corresponding receivers have been activated. 22 When this message is used in response to an Abis-Connect Ack message, the BTS does 23 not need to send this message if the transmitters(s)/receiver(s) are not turned on at the 24 BTS (i.e., the radio transmission on the forward link has not begun for the indicated 25 cells). 26

Multiple instances of this message may be sent relative to a single Abis connection if, for 27 instance, transmitter(s)/receiver(s) are activated at different times; however, all cells 28 referenced within a single instance of this message shall be attached to the same Abis 29 connection. 30

The BSC stops the instance of timer Tchanstatb for that Abis connection when 31 Abis-Traffic Channel Status message(s) have been received containing references to all 32 cells added to the Abis connection by the Abis-Connect message. 33

Please refer to section 6.2.18, “Abis-Traffic Channel Status,” for the format and content 34 of this message. 35


None. 37 38

39


21

5.1.12 Successful Mobile Originating Call 1

This section describes the call flow associated with an MS call origination in the IS-2000 2 system. 3

Figure 5.1.12-1 Mobile Originating Call 4

5

a. The MS transmits an Origination Message, with layer 2 6 acknowledgement required, over the access channel of the air 7 interface to the BTS. Then the BTS sends an Abis-ACH Msg 8 Transfer including the Origination message frame in Abis signaling 9 interface. 10

MS BTS MSC

Origination

Complete L3 Info: CM Service Req.

Assignment Request

ExtendedChannel Assignment

Service Connect

Service Connect Completion

Assignment Complete

BSCBS

Abis-Connect

Abis-Connect Ack

Null Traffic Abis-IS-2000 FCH Fwd (Null Data)

Abis-IS-2000 FCH Rvs (Idle)

Traffic Channel Preamble Abis-IS-2000 FCH Rvs (T-CH Preamble)

Abis-IS-2000 FCH Fwd (BS Ack Order)BS Ack Order

Idle Tch Data Frames Abis-IS-2000 FCH Rvs (Idle)

MS Ack Order Abis-IS-2000 FCH Rvs (MS Ack Order)

Abis-IS-2000 FCH Fwd (SCM)

Abis-IS-2000 FCH Rvs (SCCM)

Abis-BTS Setup

Abis-ACH Msg. Transfer (ORM)

Abis-PCH Msg. Transfer (ECAM)

a

T303

T10

Time Comment

Abis-BTS Setup Ack

Tsetupb

Tconnb

BS Ack Order Abis-PCH Msg Transfer (BS Ack Order)b

c

d

e

f

g

hi

j

k

l

m

n

o

p

q

r


22

b. The BTS may acknowledge the receipt of the Origination Message 1 with a Base Station Acknowledgment Order to the MS, or will send 2 this Base Station Acknowledgment Order to the MS encapsulated in 3 the Abis-Paging Channel Message Transfer from the BSC. 4

c. The BSC constructs the CM Service Request message, places it in the 5 Complete Layer 3 Information message, and sends the message to the 6 MSC and starts timer T303. If the BSC requested a preferred 7 terrestrial circuit in the CM Service Request message and the MSC 8 can support that terrestrial circuit, the MSC shall use the same 9 terrestrial circuit in the Assignment Request message. Otherwise, the 10 MSC may assign a different terrestrial circuit. 11

d. The MSC sends an Assignment Request message to the BSC to 12 request assignment of radio resources. This message will include 13 information on the terrestrial circuit, if one is to be used between the 14 MSC and the BSC. The MSC then starts timer T10. Upon the receipt 15 of the Assignment Request message, the BSC stops timer T303. 16

e. The BSC sends an Abis-BTS Setup message to the BTS to request 17 allocation of radio resource at the BTS. The BSC starts timer 18 Tsetupb. This step can occur any time after receipt of the 19 Origination message from the BTS. 20

f. If resources are available, the BTS responds with an Abis-Connect 21 message. The BTS starts timer Tconnb. 22

g. The BSC sends Abis-Connect Ack message to the BTS. The BTS 23 stops timer Tconnb. 24

h. The BTS sends Abis-BTS Setup Ack to the BSC to acknowledge the 25 Abis-BTS Setup. If the BSC requested a preferred Walsh code in the 26 Abis-BTS Setup message and the BTS can support this Walsh code 27 assignment then the BTS includes this same Walsh code in the 28 Abis-BTS Setup Ack message. Otherwise the BTS may allocate a 29 different Walsh code assignment. The BSC stops timer Tsetupb. 30

i. The BSC transmits the Abis-IS-2000 FCH Fwd message including 31 Null Data to let the BTS send Null traffic data toward the MS. Then 32 the BTS begin sending Null Traffic data for synchronizing between 33 the BTS and the MS. The BTS may have a function that enables to 34 send a Null Traffic data for synchronization between the BTS and the 35 MS. BSC can notify whether the BTS has the function or not by 36 sending Null Traffic. 37


23

j. The BTS sends Abis-IS-2000 FCH Rvs message including Idle data 1 to the BSC. 2

k. The BSC sends an Abis-PCH Msg Transfer including Extended 3 Channel Assignment message to the BTS. The BTS sends an 4 Extended Channel Assignment message to the MS over the paging 5 channel of the radio interface (with the MS address) to initiate the 6 establishment of a radio traffic channel. 7

l. The MS begins sending the traffic channel preamble (TCH Preamble) 8 to the BTS over the designated reverse traffic channel. Then the BTS 9 transmits this preamble with an Abis-IS-2000 FCH Rvs message. 10

m. Once the BSC acquires the reverse traffic channel, it sends an 11 Abis-IS-2000 FCH Fwd message including a Base Station 12 Acknowledgement Order with layer 2 acknowledgement required, to 13 the MS over the forward traffic channel. 14

n. After receiving a BS Ack Order message, the MS begins sending Idle 15 TCH Data Frames over the reverse traffic channel. Then the BTS 16 transmits this frame message with an Abis-IS-2000 FCH Rvs 17 message. 18

o. The MS Ack Order message is sent from the MS, and then the BTS 19 transmits it to the BSC with an Abis-IS-2000 FCH Rvs message. 20

p. The BSC then sends the Abis-IS-2000 FCH Fwd message including 21 the Service Connect message to the BTS specifying the service 22 configuration for the call. Then the BTS transmits the Service 23 Connect message to the MS. The MS begins processing traffic in 24 accordance with the specified service configuration. 25

q. On receipt of the Service Connect message, the MS responds with a 26 Service Connect Completion message. Then the BTS transmits it 27 with an Abis-IS-2000 FCH Rvs message. 28

r. After the radio traffic channel and circuit have both been established 29 and fully interconnected, the BSC sends the Assignment Complete 30 message to the MSC and considers the call to be in conversation 31 state. 32

The MSC stops timer T10 upon receipt of the Assignment Complete 33 message. 34

35


24

1


25

5.2 Mobile Terminated Call 1

The following subsections describe the procedure for establishing a call through a mobile 2 terminated action. 3

Mobile terminated call setup involves exchange of the following BSC-BTS messages: 4

Abis-PCH Message Transfer 5

Abis-PCH Message Transfer Ack 6

Abis-BTS Setup 7

Abis-Connect 8

Abis-Connect Ack 9




Abis-ACH Message Transfer 13

Abis-ACH Message Transfer Ack 14

Abis-Traffic Channel Status 15

16

5.2.1 Abis-PCH Message Transfer 17

See section 5.1.9. 18

19

5.2.2 Abis-PCH Message Transfer Ack 20


22

5.2.3 Abis-BTS Setup 23


25



28




26

1



4

5.2.7 Abis-IS-2000 FCH Forward 5


7

5.2.8 Abis-IS-2000 FCH Reverse 8


10

5.2.9 Abis-ACH Message Transfer 11


13

5.2.10 Unused section 14

15

16


See section 5.1.11. 18 19


27

5.2.12 Successful Mobile Terminated Call 1 This section describes the call flow associated with a mobile station call termination in the 2 IS-2000 system. 3

MS BTS MSC Time Comment

a

b

cd

fg

Paging Request

BSC

h

k

i

l

m

n

o

Abis-PCH Msg. Transfer (GPM)General Page

Complete L3 Info:Paging Response

p

q

r

stu

Page Response Abis-ACH Msg. Transfer (PRM)

BS Ack Order

Assignment RequestAbis-BTS Setup

Abis-Connect

Abis-Connect Ack

Abis-IS-2000 FCH Fwd (Null Data)Null Traffic

Abis-IS-2000 FCH Rvs (Idle)Abis-PCH Msg. Transfer (ECAM)

ExtendedChannel Assignment

TCH Preamble Abis-IS-2000 FCH Rvs (Preamble)Abis-IS-2000 FCH Fwd (BS Ack)BS Ack Order

Idle Tch Data Frames Abis-IS-2000 FCH Rvs (Idle)

MS Ack Order Abis-IS-2000 FCH Rvs (MS Ack)

Abis-IS-2000 FCH Fwd (SCM)Service Connect

Serv. Con. Completion Abis-IS-2000 FCH Rvs (SCCM)Assignment Complete

Abis-IS-2000 FCH Fwd (AWIM)Alert with Info

MS Ack Order Abis-IS-2000 FCH Rvs (MS Ack)

Connect Order Abis-IS-2000 FCH Rvs (Connect Order)

Abis-IS-2000 FCH Fwd (BS Ack)BS Ack OrderConnect

v

w

xy

jAbis-BTS Setup Ack

e

Tsetupb

Tconnb

T303

T10

T301

4

Figure 5.2.12-1 Mobile Terminated Call 5

6


28

a. The MSC sends the Paging Request message to the BSC to initiate a 1 mobile terminated call setup scenario. 2

b. The BSC constructs a General Page Message (GPM), places the 3 message into an Abis-PCH Msg Transfer Message and sends the 4 Abis-PCH Msg Transfer Message to the BTS. The BTS sends the 5 GPM to the MS over the paging channel. The BSC may send this 6 message to multiple BTSs managed by this BSC. In the following 7 description, it is assumed that the BSC sends this message to single 8 BTS. 9

c. The MS acknowledges the page by transmitting a Page Response 10 Message (PRM) to the BTS over the access channel. Upon receipt of 11 this message, the BTS places this message into an Abis-ACH Msg 12 Transfer Message and sends it to the BSC. 13

d. The BTS acknowledges the receipt of the PRM from the MS by 14 sending a Base Station Acknowledgement Order to the MS. 15

e. The BSC sends the Complete Layer 3 Information message 16 containing the Paging Response message to the MSC. The BSC starts 17 timer T303. The BSC may request the MSC to allocate a preferred 18 terrestrial circuit. 19

f. The MSC sends an Assignment Request message to request 20 assignment of radio resources. The message will also include 21 terrestrial circuit if one it to be used between the MSC and the BSC. 22 The MSC then starts timer T10. 23

If the BSC requested a preferred terrestrial circuit in the CM Service 24 Request message and the MSC can support that terrestrial circuit, the 25 MSC shall use the same terrestrial circuit in the Assignment Request 26 message. Otherwise the MSC may assign a different terrestrial circuit. 27 Upon receipt of the Assignment Request message from the MSC, the 28 BSC stops timer T303. 29

g. The BSC sends an Abis-BTS Setup message to the BTS to request 30 allocation of radio resources at the BTS. The BSC may allocate a 31 code channel and include it in the Abis-BTS Setup. The BSC starts 32 timer Tsetupb. 33

h. Upon receipt of Abis-BTS Setup message, the BTS allocates radio 34 resources and sends Abis-Connect message to initiates an Abis 35


29

connection and to report the result of resource allocation. The BTS 1 starts timer Tconnb. 2

i. The BSC replies with an Abis-Connect Ack message to complete the 3 Abis connection. The BTS stops timer Tconnb. 4

j. The BTS sends Abis-BTS Setup Ack to acknowledge the Abis-BTS 5 Setup. If the BSC requested a preferred Walsh code in the Abis-BTS 6 Setup message and the BTS can support this Walsh code assignment 7 then the BTS includes this same Walsh code in the Abis-BTS Setup 8 Ack message. Otherwise the BTS may allocate a different Walsh 9 code assignment. The BSC stops timer Tsetupb. 10

k. The BSC sends an Abis-IS-2000 FCH Fwd (Null Traffic Data) 11 message to the BTS. The BTS starts sending Null Traffic Data to the 12 mobile station. This allows the mobile station to acquire the FCH 13 (Fundamental channel). The BTS may have a function that enables to 14 send a Null Traffic data for synchronization between the BTS and the 15 MS. BSC can notify whether the BTS has the function or not by 16 sending Null Traffic.. 17

l. Upon receiving the first Abis-IS-2000 FCH Fwd (Null Traffic Data) 18 message, the BTS starts to send Abis-IS-2000 FCH Rvs (Idle frame) 19 message to the BSC. 20

m. The BSC sends an Extended Channel Assignment message to assign 21 the FCH. 22

n. The MS starts to send the Traffic Channel Preamble. Upon receiving 23 the Traffic Channel Preamble, the BTS stops sending the idle frames 24 and starts sending the traffic frames containing the Traffic Channel 25 Preamble. 26

o. The BSC sends the BS Ack Order to the MS via the BTS in the 27 Abis-IS-2000 FCH Fwd message. 28

p. The MS stops transmitting the Traffic Channel Preamble and starts to 29 transmit idle traffic channel data frames upon receipt of the BS Ack 30 order. 31

q. The MS sends the MS Ack Order to acknowledge the BS Ack order. 32 This is sent by the BTS to the BSC in the Abis-IS-2000 FCH Rvs 33 message. 34


30

r. The BSC sends the Service Connect Message (SCM) to the MS 1 specifying the service configuration for the call. This message is sent 2 by the BSC to the BTS in the Abis-IS-2000 FCH Fwd message. The 3 MS begins processing traffic in accordance with the specified service 4 configuration. 5

s. Upon receipt of the Service Connect Message (SCM), the MS 6 responds with a Service Connect Completion Message (SCCM). 7 Upon receipt of this message, BTS sends an Abis-IS-2000 FCH Rvs 8 message containing this message to the BSC. 9

t. After the radio traffic channel and circuit have both been established, 10 the BSC sends the Assignment Complete message to the MSC. The 11 MSC stops timer T10 upon the receipt of the Assignment Complete 12 message from the BSC and starts timer T301. 13

u. The BSC sends Alert with Information Message (AWIM) to the MS 14 to cause ringing at the MS. This message is sent by the BSC to BTS 15 in the Abis-IS-2000 FCH Fwd message. 16

v. The MS acknowledges the reception of the Alert with Information 17 Message by transmitting the MS Ack Order. 18

w. When the call is answered at the MS, a Connect Order, with 19 acknowledgment required, is transmitted to the BSC via the BTS. 20

x. The BSC acknowledges the Connect Order with the BS Ack order. 21

y. The BSC sends a Connect message to the MSC to indicate that the 22 call has been answered at the MS. At this point, the call is considered 23 stable and in the conversation state. The MSC stops timer T301 upon 24 receipt of the Connect message from the BSC. 25

26

27


31

5.3 Call Clearing 1

MS, BTS, BSC or MSC will initiate call clearing procedure. 2

The Following messages are exchanged between BSC and BTS. 3



Abis-BTS Release 6

Abis-BTS Release Ack 7

Abis-BTS Remove 8

Abis-BTS Remove Ack 9

Abis-BTS Release Request 10 11

5.3.1 Call Clearing initiated by MS 12 13

5.3.1.1 Successful Clear Scenarios 14

For a normal clearing that is initiated by the MS, the MS will send a Release Order to the 15 BTS. The BTS shall send an Abis-IS-2000 FCH Rvs message that contains the Release 16 Order message to the BSC. Then BSC sends Clear Request message to the MSC and 17 starts timer T300 to wait for the Clear Command message from the MSC. For packet 18 data calls, call clearing does not normally clear the service session. The service session 19 will be cleared using procedures in this section for conditions such as MS power down, 20 termination of the PPP session by the mobile or the network, etc. 21

In response to the Clear Command message from the MSC, the BSC sends an 22 Abis-IS-2000 FCH Fwd message containing the Release Order message. The BTS 23 sends this to the MS on the forward traffic channel to wait for the Abis-Remove Ack 24 message from the BTS. 25

If the BTS receives the Abis-BTS Release message, the BTS starts to releases the radio 26 resource, sends Abis-Remove message to the BSC and starts timer Tdisconb. 27

In response to the Abis-Remove message from the BTS, the BSC sends Abis-Remove 28 Ack message to the BTS. The BTS will stop timer Tdisconb. 29

Then the BTS sends an Abis-BTS Release Ack message to the BSC to acknowledge the 30 completion of the releasing the radio resources. 31

If the BSC receives the Abis-BTS Release Ack message from the BTS, the BSC will stop 32 timer Tdrptgtb and sends a Clear Complete message to the MSC. Then the BSC 33 releases the related terrestrial circuit to the BTS, if allocated. The MSC stops timer 34 T315 upon receipt of the Clear Complete message. The MSC releases the underlying 35 transport connection. 36

The call flow scenarios are illustrated in section 5.3.4, 5.3.5 and 5.3.6.. 37


32

5.3.1.2 Unsuccessful Call Clearing Procedures 1

Each node will supervise and detect the unnecessary reserved resource spontaneously, 2 and release it individually. 3

5.3.1.3 Abis-IS-2000 FCH Rvs 4

See 5.1.8. 5

5.3.1.3.1 Successful Operation 6

See 5.1.8.1. 7

8

5.3.1.3.2 Failure Operation 9

See 5.1.8.2. 10

11

5.3.1.4 Abis-IS-2000 FCH Fwd 12

See 5.1.7. 13


See 5.1.7.1. 15

16


See 5.1.7.2. 18

19

5.3.1.5 Abis-BTS Release 20

In response to the Clear Command message from the MSC, the BSC sends an 21 Abis-IS-2000 FCH Fwd message containing the Release Order message and then the 22 BSC sends an Abis-BTS Release message to the BTS. 23


The BSC, after sending an Abis-BTS Release message to the BTS and starts timer 25 Tdrptgtb to wait for the Abis-Release Ack message from the BTS. 26

Upon receipt of the Abis-BTS Release message, the BTS releases the associated radio 27 resources. The BTS sends an Abis-BTS Release Ack message to the BSC to acknowledge 28 the clearing of resources at the BTS. 29


32


33


If the BSC fails to receive an Abis-BTS Release Ack message before the expiration of 2 timer Tdrptgtb, the BSC may resend the Abis-BTS Release message to the BTS. 3

4

5.3.1.6 Abis-BTS Release Ack 5

The Abis-BTS Release Ack message is used by BTS to respond to a request that it 6 releases the radio resources in the BTS. 7


Upon receipt of the Abis-BTS Release message, the BTS releases the associated radio 9 resources. The BTS sends an Abis-BTS Release Ack message to the BSC to acknowledge 10 the clearing of resources at the BTS. 11

12


None 14

15

5.3.1.7 Abis-BTS Remove 16

In response to the Abis-BTS Release message from the BSC, the BTS sends an Abis-BTS 17 Remove message to the BSC and starts to releases the radio resource. 18


The BTS, after sending an Abis-BTS Remove message to the BSC and starts timer 20 Tdisconb to wait for the Abis-Remove Ack message from the BSC. 21

Then the BSC sends an Abis-BTS Remove Ack message to the BTS to acknowledge the 22 receiving of the message. 23

24


If an Abis-BTS Remove Ack message is not received from the BSC while timer Tdisconb 26 is active, the BTS may choose to resend a Abis-BTS Remove message to the BSC. 27

28

5.3.1.8 Abis-BTS Remove Ack 29

The Abis-BTS Remove Ack message is used by BSC to confirm the reception of the 30 Abis-Remove message in BSC. 31


34


The BSC sends an Abis-BTS Remove Ack message to the BTS to acknowledge the 2 receiving of Abis-BTS Remove message . 3

4


None 6

7 8


35

5.3.2 Call Clearing initiated by BS/MSC 1

2


If some internal BSC failure occurs, then the BSC will initiate call clearing. 4

The BSC sends Clear Request message to the MSC and starts timer T300 to wait for the 5 Clear Command message from the MSC. 6

The MSC is responsible for clearing any A1, A2, and/or A5 connections associated with 7 the call. To release all allocated resources, the MSC sends a Clear Command message to 8 the BSC and starts timer T315. The BSC responds with a Clear Complete message and 9 stop timer T300. 10

Then the BSC sends an Abis-IS-2000 FCH Fwd message containing the Release Order 11 message and the Release Order will be transferred to MS on the IS-2000 FCH Fwd 12 channel. 13

If the BTS receives Release Order from MS, the BTS sends Abis-IS-2000 FCH Rvs 14 message that contains the Release Order message to the BSC. 15

Then the BSC sends an Abis-BTS Release message to the BTS and starts timer Tdrptgtb 16 to wait for the Abis-Remove Ack message from the BTS. 17

If the BTS receives the Abis-BTS Release message, the BTS starts to releases the radio 18 resource, sends Abis-Remove message to the BSC and starts timer Tdisconb. 19



If the BSC receives the Abis-BTS Release Ack message from the BTS, the BSC will stop 24 timer Tdrptgtb and sends a Clear Complete message to the MSC. Then the BSC 25 releases the related terrestrial circuit to the BTS, if allocated. And the MSC stops timer 26 T315 upon receipt of the Clear Complete message. The MSC releases the underlying 27 transport connection. 28

The call flow scenarios are illustrated in section 5.3. 29


Each node will detect the unnecessary reserved resource and release it individually. 31

32

5.3.2.3 Abis-IS-2000 FCH Rvs 33

See 5.1.8. 34


See 5.1.8.1 36

37


36


See 5.1.8.2 2

3

5.3.2.4 Abis-IS-2000 FCH Fwd 4

See 5.1.7. 5


See 5.1.7.1 7

8


See 5.1.7.2. 10

11


See 5.3.1.5 13


See 5.3.1.5.1. 15

16


See 5.3.1.5.2. 18

19


See 5.3.1.6. 21


See 5.3.1.6.1 23

24


None 26

27


See 5.3.1.7. 29


37


See 5.3.1.7.1. 2

3


See 5.3.1.7.1. 5

6 7


38

5.3.3 Call Clearing initiated by BTS 1

2


If the MS is not active (powered off) or if for any reason the radio channel failed between 4 the MS and the BTS or if some internal BTS failure occurs, then the BTS will initiate call 5 clearing by sending Abis-BTS Release Request and starts Tdrptgtb. 6

If the BSC receives Abis-BTS Release Request message, the BSC sends Clear Request 7 message to the MSC and starts timer T300 to wait for the Clear Command message from 8 the MSC. 9

The MSC is responsible for clearing any A1, A2, and/or A5 connections associated with 10 the call. To release all allocated resources, the MSC sends a Clear Command message to 11 the BSC and starts timer T315. The BSC stops timer T300. 12

Then the BSC sends an Abis-IS-2000 FCH Fwd message containing the Release Order 13 message and the Release Order will be transferred to MS on the IS-2000 FCH Fwd 14 channel. 15

If the BTS receives Release Order from MS, the BTS sends Abis-IS-2000 FCH Rvs 16 message that contains the Release Order message to the BSC. 17

Then the BSC sends an Abis-BTS Release message to the BTS and starts timer Tdrptgtb 18 to wait for the Abis-Remove Ack message from the BTS. 19

If the BTS receives the Abis-BTS Release message, the BTS stops timer Tdrptgtb , starts 20 to releases the radio resource and sends Abis-Remove message to the BSC and starts 21 timer Tdisconb. 22



If the BSC receives the Abis-BTS Release Ack message from the BTS, the BSC will stop 27 timer Tdrptgtb and sends a Clear Complete message to the MSC. Then the BSC 28 releases the related terrestrial circuit to the BTS, if allocated. And the MSC stops timer 29 T315 upon receipt of the Clear Complete message. The MSC releases the underlying 30 transport connection. 31

The call flow scenarios are illustrated in section 5.3. 32


Each node will detect the unnecessary reserved resource and release it individually. 34

35

5.3.3.3 Abis-BTS Release Request 36

If the MS is not active (powered off) or if for any reason the radio channel failed between 37 the MS and the BTS or if some internal BTS failure occurs, then the BTS will send 38 Abis-BTS Release Request message to the BSC in order to initiate call clearing. 39


39


The BTS, after sending an Abis-BTS Release Request message to the BSC and starts 2 timer Trelreqb to wait for the Abis-Release message from the BSC. 3

If the BTS receives the Abis-BSC Release message, then the BTS stops Trelreqb and 4 starts to releases the radio resource. 5

6


If an Abis-BTS Release message is not received from the BSC while timer Trelreqb is 8 active, the BTS may choose to resend a Abis-BTS Release Request message to the BSC. 9

10

5.3.3.4 Abis-IS-2000 FCH Rvs 11

See 5.1.8. 12


See 5.1.8.1 14

15


See 5.1.8.2 17

18

5.3.3.5 Abis-IS-2000 FCH Fwd 19

See 5.1.7. 20


See 5.1.7.1 22

23


See 5.1.7.2 25

26


See 5.3.1.5 28


See 5.3.1.5.1. 30


40

1


See 5.3.1.5.2. 3

4


See 5.3.1.6. 6


See 5.3.1.6.1 8

9


None 11

12


See 5.3.1.7. 14


See 5.3.1.7.1. 16

17


See 5.3.1.7.1. 19

20

5.3.3.9 Abis-BTS Remove Ack 21

See 5.3.1.8. 22


See 5.3.1.8.1. 24

25


None 27 28

29


41

5.3.4 Call Clearing initiated by MS 1

This section provides the call flow diagram for a call clearing operation initiated by MS. 2

3

4

5 6 7 8 9 10 11 12 13 14 15 16 17 18 19

20

Figure 5.3.4-1 Call Clearing initiated by MS 21

a. The MS initiates call clearing by transmitting a Release Order over 22 the reverse traffic channel. In response to the order, BTS sends an 23 Abis-IS-2000 FCH Rvs message containing the Release Order 24 message to the BSC. 25

b. The BSC then sends the Clear Request message to the MSC to 26 initiate the call clear transaction. Timer T300 is started by the BSC. 27

c. The MSC sends a Clear Command message to the BSC to instruct the 28 BSC to release the associated dedicated resource (such as terrestrial 29 circuit) and starts timer T315. The BSC stops timer T300. 30

d. In response to the Clear Command message from the MSC, the BSC 31 sends an Abis-IS-2000 FCH Fwd message containing the Release 32 Order message. The BTS sends the Release Order message to the MS 33 over the forward traffic channel 34

MS BTS MSC

Clear Request

Clear Command

Clear Complete

BSC

BS

Release Order Abis-IS-2000 FCH Rvs (Release Order)

Abis-IS-2000 FCH Fwd (Release Order) )

Release Order

Abis-Remove

Abis-Remove Ack

T300

T315

a

b

c

d

e

f

g

Time

Abis-BTS Release

Abis-BTS Release Ack

i

h

Tdisconb

Tdrptgtb


42

e. The BSC then sends an Abis-BTS Release message to the BTS and 1 starts Tdrptgtb. 2

f. The BTS releases the radio resource and sends Abis Remove message 3 to the BSC. The BTS starts Tdisconb. 4

g. In response to the Abis-Remove message from the BTS, BSC sends 5 an Abis-Remove Ack message to the BTS. Upon receipt of the 6 Abis-Remove Ack message the BTS stops timer Tdisconb. 7

h. The BTS sends an Abis-BTS Release Ack message to the BSC to 8 acknowledge the Abis removal. Upon receipt of the Abis-BTS 9 Release Ack message the BSC stops timer Tdrptgtb. 10

i. The BSC sends a Clear Complete message to the MSC. Then BSC 11 releases the related terrestrial circuit to the BTS, if allocated. And 12 the MSC stops timer T315 upon receipt of the Clear Complete 13 message. The MSC releases the underlying transport connection. 14

15 16


43

5.3.5 Call Clearing initiated by BSC/MSC 1

This section provides the call flow diagram for a call clearing operation initiated by 2 BSC/MSC. 3

4

5

6

7

8 9

10

11

12

13

14

Figure 5.3.5-1 Call Clearing initiated by BSC/MSC 15

a. In the case where the BSC detects some failures related the call, the 16 BSC sends a Clear Request message to the MSC. The BSC starts 17 timer T300 and waits for the Clear Command from the MSC (step b). 18 A Call Clearing flow initiated by BSC starts from this step. 19

b. The MSC and sends a Clear Command message to instruct the BSC 20 to release the associated dedicated resource (such as terrestrial 21 circuit) and starts timer T315. In the case of a Call Clearing 22 initiated BS, the BSC stops timer T300. A Call Clearing flow 23 initiated by MSC starts from this step. 24

c. In response to the Clear Command message from the MSC, the BSC 25 sends Abis-IS-2000 FCH Fwd containing the Release Order message. 26

BTS MSC BSC

BS

Abis-IS-2000 FCH Fwd (Release Order)

Abis-IS-2000 FCH Rvs (Release Order)

Abis-Remove

Abis-Remove Ack

a

b

c

d

e

f

g

Time

Abis-BTS Release

i


MS BTS MSC

Clear Request

Clear Command

Clear Complete

BSC

BS

Release Order

Release Order

T300

T315

a

b

c

Time

Tdrptgtb

Tdisconb

h


44

The BTS sends the Release Order message to the MS over the 1 forward traffic channel. 2

d. The MS replies with a Release Order over the reverse traffic channel. 3 In response to the order, BTS sends an Abis-IS-2000 FCH Reverse 4 containing the Release Order message to the BSC. 5

e. The BSC then sends an Abis-BTS Release message to the BTS and 6 starts Tdrptgtb. 7


g. In response to the Abis Remove message from the BTS, the BSC 10 sends an Abis Remove Ack message to the BTS. Then the BSC 11 releases the related terrestrial circuit to the BTS, if allocated. If the 12 BTS receives the Abis-Remove Ack message, the BTS stops timer 13 Tdisconb. 14

h. The BTS sends an Abis-BTS Release Ack message to the BSC to 15 acknowledge the Abis removal. If the BSC receives the Abis-Release 16 Ack message, BSC stops timer Tdrptgtb. 17

i. Upon receipt of the Abis BTS Release Ack message, the BSC sends 18 the Clear Complete message to the MSC. The MSC stops timer T315 19 upon receipt of the Clear Complete message. The MSC releases the 20 underlying transport connection. 21

22


45

5.3.6 Call Clearing initiated by BTS 1

This section provides the call flow diagram for a call clearing operation initiated by the 2 BTS. 3

4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Figure 5.3.6-1 Call Clearing initiated by BTS 25

a. In the case of a radio channel failure between the MS and the BTS, or 26 if the MS is not active, the BTS sends an Abis-BTS Release Request 27 message to BSC and the BTS starts timer Trelreqb. In response to 28 the message the BSC sends a Clear Request message to the MSC. 29 The BSC starts timer T300 and waits for the Clear Command from 30 the MSC. A Call Clearing flow initiated by BTS starts from this 31 step. 32

b. The MSC starts timer T315 and sends a Clear Command message to 33 instruct the BSC to release the associated dedicated resource (such as 34 terrestrial circuit). The BSC stops timer T300. 35

c. In response to the Clear Command message from the MSC, the BSC 36 sends Abis-IS-2000 FCH Fwd containing the Release Order message. 37 The BTS sends the Release Order message to the MS over the 38 forward traffic channel. 39

MS BTS MSC

Clear Request

Clear Command

Clear Complete

BSC

BS

Release Order Abis-IS-2000 FCH Fwd (Release Order)

Abis-IS-2000 FCH Rvs (Release Order) )

Release Order

Abis-Remove

Abis-Remove Ack

T300

T315

a

b

c

d

e

f

g

Abis-BTS Release

Abis-BTS Release Request

Abis-BTS Release ACK h

Tdisconb Tdrptgtb

Trelreqb

Time

i


46

d. The MS replies with a Release Order over the reverse traffic channel. 1 In response to the order, BTS sends an Abis-IS-2000 FCH Rvs 2 containing the Release Order message to the BSC. 3

e. The BSC then sends an Abis-BTS Release message to the BTS and 4 starts Tdrptgtb. If the BTS receives Abis-BTS Release message from 5 the BTS, the BTS stops timer Trelreqb. 6


g. In response to the Abis Remove message from the BTS and the BSC 9 sends an Abis Remove Ack message to the BTS and returns a Clear 10 Complete message to the MSC. Then the BSC releases the related 11 terrestrial circuit to the BTS, if allocated. If the BTS receives the 12 Abis-Remove Ack message, the BTS stops timer Tdisconb. 13

h. The BTS sends an Abis-BTS Release Ack message to the BSC to 14 acknowledge the Abis removal. If the BSC receives the Abis-Release 15 Ack message, the BSC stops timer Tdrptgtb. 16

i. Upon receipt of the Abis-BTS Release Ack message, the BSC sends 17 the Clear Complete message to the MSC. The MSC stops timer T315 18 upon receipt of the Clear Complete message. The MSC releases the 19 underlying transport connection. 20

21


47

5.4 Handoff 1

This section describes handoff procedure using Abis interface within the BS. TIA/EIA/IS-2001 2

5.4.1 Abis-BTS Interface Procedures and Messages 3

This section describes the messages and procedures used Abis connection to support 4 soft/softer handoff, Hard handoff. 5

5.4.1.1 Abis-BTS Interface Messages 6

This section describes the messages and procedures used Abis connection to support BTS 7 soft/softer handoff. 8

These messages are: 9

Abis-BTS Setup 10


Abis-Connect 12

Abis-Connect Ack 13

Abis-IS-2000 FCH Forward 14

Abis-IS-2000 FCH Reverse 15

Abis-Traffic channel status 16

Abis-BTS-Release 17

Abis-BTS-Release Ack 18

Abis-Remove 19

Abis-Remove Ack 20

21

5.4.1.1.1 Abis-BTS Setup 22

The Abis-BTS Setup message is used by the BSC to request that a target BTS allocate 23 resources in one or more cells for support of a call association. 24

25

5.4.1.1.1.1 Successful Operation 26

When the BSC decides that one or more cells at a target BTS are needed to support one or 27 more physical channel connections for a call, the BSC sends an Abis-BTS Setup message 28 to the target BTS to indicate the resources required. The BSC then starts timer Tsetupb. 29

Please refer to section 6.1.5 “Abis-BTS Setup,” for the format and content of this 30 message. 31

32


48

5.4.1.1.1.2 Failure Operation 1

If timer Tsetupb expires, the BSC may choose to resend the Abis-BTS Setup message. 2 3

5.4.1.1.2 Abis-BTS Setup Ack 4

The Abis-BTS Setup Ack message is used by the target BTS to respond to a request that 5 it allocates resources in one or more cells for support of one or more physical channel 6 connections for a call association. 7

8 5.4.1.1.2.1 Successful Operation 9

When the target BTS receives an Abis-BTS Setup message, it determines what internal 10 resources are needed to support the requested physical channels for the call association. 11 Once those resources are allocated and the Abis-Connect Ack message(s) has been 12 received, the target BTS responds by sending an Abis-BTS Setup Ack message to the 13 BSC. 14

Please refer to section 6.1.6 ”Abis-BTS Setup Ack” for the format and content of this 15 message. 16

17 5.4.1.1.2.2 Failure Operation 18

None. 19 20

5.4.1.1.3 Abis -Connect 21

The Abis-Connect message is sent from the target BTS to the BSC to initiate or add cells 22 to one or more Abis user traffic connection. An Abis -Connect Ack message is expected 23 in response. 24


Upon receiving the Abis Signaling Address information, the receiving BTS begins the 27 process of establishing the Abis signaling connection with the BSC. The Abis Signaling 28 Address is used by the target BTS to allocate a logical circuit to be used for Abis 29 signaling. The SDU ID identifies the particular instance of the SDU function. 30

Following the establishment of the Abis signaling link, the Abis-Connect message is sent 31 from the target BTS to the entity at the other end. The target BTS expects an 32 Abis-Connect Ack message indicating the result of processing the Abis-Connect message 33 and, therefore, starts timer Tconnb. When the Abis user traffic connection(s) is 34 established, traffic packets are exchanged to verify that the two entities can communicate 35 via the Abis user traffic connection(s). 36

Please refer to section 6.1.12 ”Abis-Connect” for the format and content of this message. 37



49

If timer Tconnb expires, the BTS may choose to resend the Abis-Connect message. 1

2

5.4.1.1.4 Abis-Connect Ack. 3

The Abis-Connect Ack message is sent from the BSC to the target BTS to indicate the 4 result of processing the Abis-Connect message. 5


After processing the Abis-Connect message from the requesting BTS, the BSC will 8 indicate success/failure to the requesting BTS by sending an Abis-Connect Ack message. 9

If the Abis-Connect Ack message indicates that Abis-Traffic Channel Status messages are 10 to be sent, then the source BSC starts timer Tchanstatb to await Abis-Traffic Channel 11 Status message(s) for all new cells on each Abis connection. One instance of this timer 12 is started for each Abis connection to which one or more cells are being added. 13

Please refer to section 6.1.13 ”Abis-Connect Ack” or the format and content of this 14 message. 15


If an instance of timer Tchanstatb expires, the BSC may assume that a failure has 18 occurred at the BTS during activation of the transmitter(s)/receiver(s) and delete the 19 unreported cells from the active set attached to the Abis connection. The BSC may then 20 send an Abis-BTS Release message to the target BTS to cleanly remove those cells from 21 the Abis connection. 22

5.4.1.1.5 Abis-Traffic Channel Status 23

The Abis-Traffic Channel Status message is used by the target BS to notify the BSC that 24 radio transmission on the forward link has begun for the indicated cells, and that the 25 corresponding receivers have been activated. This message is sent when the 26 Abis-Connect Ack message indicates that it is requested. 27


When the target BS needs to notify the BSC of a status change relative to a specific set of 30 cells on one Abis connection, it sends an Abis-Traffic Channel Status message. 31

This message can be used to note that the indicated set of cells has begun radio 32 transmission on the forward link and that the corresponding receivers have been activated. 33 When this message is used in response to an Abis-Connect Ack message, the target BS 34 does not need to send this message if the transmitters(s)/receiver(s) are not turned on at 35 the target BS (i.e., the radio transmission on the forward link has not begun for the 36 indicated cells). 37

Multiple instances of this message may be sent relative to a single Abis connection if, for 38 instance, transmitter(s)/receiver(s) are activated at different times; however, all cells 39


50

referenced within a single instance of this message shall be attached to the same Abis 1 connection. 2

The BSC stops the instance of timer Tchanstatb for that Abis connection when 3 Abis-Traffic Channel Status message(s) have been received containing references to all 4 cells added to the Abis connection by the Abis-Connect message. 5

Please refer to section 6.1.18, “Abis-Traffic Channel Status,” for the format and content 6 of this message. 7


None. 10 11

5.4.1.1.6 Abis-IS-2000 FCH Forward 12

This message is sent from the BSC to the target BTS on the Abis IS-2000 user traffic 13 subchannel for subchannel of type “FCH” (Fundamental Channel). It contains the 14 Forward airframe for the served MS along with control information for the target BTS. 15


This message is sent from BSC to the target BTS on Abis IS-2000 user traffic subchannel 18 connections of type “FCH” (Fundamental Channel). FCH messages are sent once every 19 20 ms. 20

The forward path message delay shall be no more than 50ms measured from the time the 21 first bit of the frame is transmitted from the BSC to the time the first bit of the frame is 22 transmitted over the air interface at the channel element for any soft handoff leg. This 23 assumes a maximum transmission and queuing delay on the Abis traffic connection of 24 5ms. However, the delay limits defined above will not be applied to satellite applications. 25

Forward Frame Sequence Number Alignment clarification: 26

The SDU function may use the PATE and Sequence Number information received in the 27 Abis-IS-2000 FCH Reverse message to ensure that all BTS's involved in soft handoff for 28 a call will simultaneously transmit identical forward air frames during identical frame 29 boundaries. 30

Please refer to section 6.1.16 “Abis-IS-2000 FCH Forward” for the format and content of 31 this message. 32


None. 35 36 5.4.1.1.7 Abis-IS-2000 FCH Reverse 37

This message is sent from the target BTS to the BSC on Abis IS-2000 user traffic 38 subchannel connections of type “IS-2000 FCH” (TIA/EIA/IS-2000 Fundamental Channel). 39


51

It contains the decoded Reverse Traffic Channel frame received from the served MS 1 along with control information. 2


This message is sent to the BSC on the Abis IS-2000 user traffic subchannel connections 5 of type “IS-2000 FCH” (TIA/EIA/IS-2000 Fundamental Channel) following the decoding 6 of the Reverse Traffic Channel frame. IS-2000 FCH frames are sent once every 20 ms. 7

The reverse path message delay shall be no more than 60 ms measured from the time the 8 last bit of the frame is received on the air interface at the channel element of any soft 9 handoff leg to the time the last bit of the frame is received at the BSC. This assumes a 10 maximum transmission and queuing delay on the Abis traffic connection of 5 ms. 11 However, the delay limits defined above will not be applied to satellite applications. 12

Forward Frame Alignment Requirements: 13

As part of the reverse-link processing, each target BTS channel element shall estimate the 14 arrival time error for the Abis-IS-2000 FCH Forward message last received and shall set 15 the PATE field of the next transmitted Abis-IS-2000 FCH Reverse message to this value. 16

In the case when no forward data has been received for an interval of time exceeding the 17 maximum range of the PATE, the PATE value shall saturate (i.e., not rollover) at the 18 maximum positive value. Positive PATE values indicates that the message arrived too 19 late to be transmitted in the correct airframe. Negative PATE values indicate that the 20 message arrived too early and therefore shall be buffered before transmission. Zero PATE 21 value indicates that the message arrived at the optimum time for processing and 22 transmission. 23

Please refer to section 6.1.17 ”Abis-IS-2000 FCH Reverse” for the format and content of 24 this message. 25


None. 28 29

5.4.1.1.7 Abis-BTS Release 30

The Abis-BTS Release message is used by the BSC to request that a target BTS 31 deallocate resources in one or more cells currently being used for support of one or more 32 physical channel connections for a call association. 33


When the BSC decides that one or more cells at a target BTS are no longer needed to 36 support one or more physical channel connections for a call association, the BSC sends an 37 Abis-BTS Release message to the target BS to indicate the resources that are no longer 38 required. The BSC then starts timer Tdrptgtb. 39

Please refer to section 6.1.7, “Abis-BTS Release” for the format and content of this 40 message. 41


52


If timer Tdrptgtb expires, the BSC may choose to resend the Abis-BTS Release message. 3

4

5.4.1.1.8 Abis-BTS Release Ack 5

The Abis-BTS Release Ack message is used by the BSC to respond to a request that it 6 deallocate resources in one or more cells currently being used for support of one or more 7 physical channel connections for a call association. 8


When the BTS receives an Abis-BTS Release message, it determines what resources are 11 no longer needed to support the call association. Once those resources are deallocated, 12 the BTS responds by sending an Abis-BTS Release Ack message to the BSC. 13

Please refer to section 6.1.8, “Abis BTS Release Ack,” for the format and content of this 14 message. 15


None. 18 19

5.4.1.1.9 Abis-Remove 20

A target BTS uses the Abis-Remove message to request that the BSC remove the 21 indicated cells from the indicated Abis connections. This might result in the entire 22 removal of an Abis traffic subchannel if the last cell on that traffic subchannel is 23 removed. 24


The BTS sends an Abis-Remove message to the BSC requesting removal of the indicated 27 cells from one or more Abis connection. The BSC will reply with an Abis-Remove Ack 28 message. If the last cell is removed from an Abis traffic subchannel, the entire Abis 29 traffic subchannel is also terminated. The BTS starts timer Tdisconb. 30

Please refer to section 6.1.14, “Abis-Remove,” for the format and content of this 31 message. 32


If the BSC does not recognize an Abis user traffic connection identified in the 35 Abis-Remove message as being associated with the Call Connection Reference value 36 included in this message, it shall send an appropriate cause for the failure in the 37 Abis-Remove Ack message. 38


53

If timer Tdisconb expires, the BTS may resend the Abis-Remove message. 1

2

5.4.1.1.10 Abis-Remove Ack 3

The Abis-Remove Ack message is used by the BSC to notify the target BS that sent the 4 Abis-Remove message of the outcome of processing the Abis-Remove message. 5


The BSC sends an Abis-Remove Ack message to the target BTS that sent the 8 Abis-Remove message to indicate the results of processing the Abis-Remove message. 9 The Cause List element, when present, indicates any exceptions. 10

Please refer to section 6.1.15, “Abis-Remove Ack,” for the format and content of this 11 message. 12


None. 15 16

17


54

5.4.2 Soft/Softer Handoff addition (Intra-BTS) 1 2

Figure 5.4.2-1 Soft/Softer Handoff addition (Intra-BTS) 3

4

a. The BSC sends an Abis-BTS Setup message to the BTS to request 5 that the specified cells be added from the call. The BSC may allocate 6 a code channel and include it in the Abis-BTS Setup. The BSC starts 7 the timer Tsetupb. 8

b. The BTS allocates internal resources related to the specified cells. 9 The BTS sends an Abis-Connect message to the SDU function of the 10 BSC. The BTS starts the timer Tconnb. 11

c. The SDU function replies with an Abis-Connect Ack message and 12 allocates internal resources. The BTS stops timer Tconnb. If the 13 BSC has chosen to be notified of the start of transmission and 14 reception at the target BTS ,the BSC will set Abis-Connect Ack 15 message indicating that Abis-Traffic Channel Status message is 16 requested, starts timer Tchanstatb. 17

d. The BTS sends Abis-BTS Setup Ack to acknowledge the Abis-BTS 18 Setup. If the BSC requested a preferred Walsh code in the 19

Abis-BTS Setup

MS BSC

Extended/General/Universal Handoff Direction Message

MS Ack Order

Handoff Completion Message

BS Ack Order

a Abis-Connect

Abis-Connect Ack

Abis-BTS Setup Ack

Time

b c d

e

f

g

h

Abis-IS-2000 FCH Fwd

Abis-IS-2000 FCH Rvs



BTS

Tconnb

Tsetupb

Abis-Traffic channel status

i

TchanstatbConditional


55

Abis-BTS Setup message and the BTS can support this Walsh code 1 assignment then the BTS includes this same Walsh code in the 2 Abis-BTS Setup Ack message. Otherwise the BTS may allocate a 3 different Walsh code assignment. The BSC stops the timer Tsetupb. 4

e. If the BSC has chosen to be notified of the start of transmission and 5 reception at the target BTS, when its SDU function and the target 6 BTS have synchronized with Abis traffic subchannel, the BTS sends 7 an Abis-Traffic Channel Status message to the BSC. The BSC stops 8 timer Tchnstatb. 9

f. The BSC sends an Extended / General / Universal Handoff Direction 10 Message to the MS to add the new cell to the active set. 11

g. The MS acknowledges receipt of the Extended / General / Universal 12 Handoff Direction Message with an MS Ack Order. 13

h. The MS indicates successful results of processing the Extended / 14 General / Universal Handoff Direction Message by sending a 15 Handoff Completion message. 16

i. The BSC acknowledges receipt of the Handoff Completion Message 17 by sending a BS Ack Order. 18

19 20


56

5.4.3 Soft/Softer Handoff addition (Inter-BTS) 1 2

Figure 5.4.3-1 Soft/Softer Handoff addition (Inter-BTS) 3

a. The BSC decides that one or more cells at the target BTS are needed 4 to support the call in soft/softer handoff. The BSC sends an 5 Abis-BTS Setup message to the target BTS to request allocation of 6 radio resources at the BTS. The BSC may allocate a code channel 7 and include it in the Abis-BTS Setup. The BSC starts the timer 8 Tsetupb. 9

b. If resources are available, the target BTS responses with 10 Abis-Connect message. The BTS starts the timer Tconnb. 11

c. The BSC replies with an Abis-Connect Ack message to complete the 12 Abis connection. The BTS stops timer Tconnb. If the BSC has 13 chosen to be notified of the start of transmission and reception at the 14 target BTS ,the BSC will set Abis-Connect Ack message indicating 15 that Abis-Traffic Channel Status message is requested, starts timer 16 Tchanstatb. 17

18

Abis-BTS Setup

M S BSCSource

BTS

Extended/G eneral/UniversalHandoff Direction M essage

M S Ack Order

Handoff Com pletion M essage

Abis-Traffic Channel Status

BS Ack Order

aAbis-Connect

Abis-Connect Ack

Abis-IS-2000 FCH Fwd( Forward Fram es)

Abis-IS-2000 FCH Rvs( Id le Fram es)

Forward Fram es

Abis-BTS Setup Ack

TargetBTS

Tim e

bcdefg

h

j

i

k

l


Ab is-IS-2000 FCH Rvs

Ab is-IS-2000 FCH Rvs


Tconnb

Tsetupb

Tchanstatb

Conditional


57

d. The target BTS sends Abis-BTS Setup Ack to acknowledge the 1 Abis-BTS Setup. If the BSC requested a preferred Walsh code in the 2 Abis-BTS Setup message and the BTS can support this Walsh code 3 assignment then the BTS includes this same Walsh code in the 4 Abis-BTS Setup Ack message. Otherwise the BTS may allocate a 5 different Walsh code assignment. The BSC stops the timer Tsetupb. 6

e. The BSC begins to send the forward frames to the target BTS. 7

f. The target BTS begins to transmit the forward frame as soon as 8 synchronization has occurred. 9

g. The target BTS begins to send reverse idle frames. The reverse 10 frames contain the timing adjustment information necessary to 11 achieve synchronization. 12

h. If the BSC has chosen to be notified of the start of transmission and 13 reception at the target BTS, when its SDU function and the target 14 BTS have synchronized the Abis traffic sub-channel, the BTS send 15 an Abis-Traffic Channel Status message to the source BTS. 16

i. The BSC sends an Extended / General / Universal Handoff Direction 17 Message to the MS to add the new cell to the active set. 18

j. The MS acknowledges receipt of the Extended / General / Universal 19 Handoff Direction Message with an MS Ack Order. 20

k. The MS indicates successful results of processing the Extended / 21 General / Universal Handoff Direction Message by sending a 22 Handoff Completion message. 23

l. The BSC acknowledges receipt of the Handoff Completion Message 24 by sending a BS Ack Order. 25

26 27


58

5.4.4 Soft/Softer Handoff Removal (Inter-BTS) 1 2

Figure 5.4.4-1 Soft/Softer Handoff Removal (Inter-BTS) 3

4

a. The BSC sends an Extended / General / Universal Handoff Direction 5 Message to the MS to drop the cell to the active set. 6

b. The MS acknowledges receipt of the Extended / General / Universal 7 Handoff Direction Message with an MS Ack Order. 8

c. The MS indicates successful results of processing the Extended / 9 General / Universal Handoff Direction Message by sending a 10 Handoff Completion message. 11

d. The BSC acknowledges receipt of the Handoff Completion Message 12 by sending a BS Ack Order. 13

e. The BSC sends an Abis-BTS-Release message to the target BTS to 14 request that the specified cells be removed from the call. The BSC 15 starts timer Tdrptgtb. 16

MS BSC Source

BTS

Extended/General/Universal Handoff Direction Message

MS Ack Order


BS Ack Order

Target BTS

Time

b

a

c

d





e

f

g

h

Abis-BTS Release

Abis-Rem ove

Abis-Remove Ack


Tdisconb

Tdrptgtb


59

f. The target BTS, upon receipt of the Abis-BTS-Release message, 1 deallocates internal resources related to the specified cells. The target 2 BTS sends an Abis-Remove message to the SDU function of the BSC 3 and starts timer Tdisconb. 4

g. The SDU function of the BSC replies with an Abis-Remove Ack 5 message and deallocates internal resources. The target BTS stops 6 timer Tdisconb. 7

h. The target BTS sends an Abis-BTS-Release Ack message to the BSC 8 to acknowledge the removal of the specified cells. The BSC stops 9 timer Tdrptgtb. 10

11


60

5.4.5 Hard Handoff (Inter-BTS) 1 2

Figure 5.4.5-1 Hard Handoff (Inter-BTS) 3

a. The BSC decides that one or more cells at the target BTS are needed 4 to support the call in hard handoff. The BSC sends an Abis-BTS 5 Setup to the target BTS to request allocation of radio resources at the 6 BTS. The BSC starts the timer Tsetupb. 7

b. If resources are available, The target BTS responses with an 8 Abis-Connect message. The target BTS starts the timer Tconnb 9

c. The BSC replies with an Abis-Connect Ack message to complete the Abis connection. The target 10 BTS stops the timer Tconnb. If the BSC has chosen to be notified of the start of transmission and 11 reception at the target BTS ,the BSC will set Abis-Connect Ack message indicating that Abis-Traffic 12 Channel Status message is requested, starts timer Tchanstatb. 13

Abis-BTS Setup

MS BSCSource

BTS

Extended/General/UniversalHandoff Direction Message

MS Ack Order


Abis-Traffic Channel Status

BS Ack Order

aAbis-Connect

Abis-Connect Ack

Abis-IS-2000 FCH Fwd( Forward Fram es)

Abis-IS-2000 FCH Rvs( Idle Fram es)Forward Fram es

Abis-BTS Setup Ack

TargetBTS

Time

bcdef

g

h

j

i

k

l





Tconnb

Tsetupb

Tchanstat

Conditional

m

n

o

p

Abis-BTS Release

Abis-Remove

Abis-Remove Ack


Tdisconb

Tdrptgtb

Reverse Fram es

q

Abis-IS-2000 FCH Rvs( Idle Fram es)


61

d. The target BTS sends an Abis-BTS Setup Ack to acknowledge the 1 Abis-BTS Setup. The target BTS may allocate a code channel. In this 2 case, the target BTS includes the allocated code channel in the 3 Abis-BTS Setup Ack. Unless the target BTS allocates a code channel, 4 the target BTS includes the code channel that has been indicated by 5 the Abis-BTS Setup (step a) in the Abis-BTS Setup Ack. The BSC 6 stops the timer Tsetupb. 7

e. The BSC begins to send the forward frames to the target BTS. 8

f. The target BTS begins to transmit the forward frames as soon as synchronization has 9 occurred. 10

g. The target BTS begins to send the reverse idle frames. The reverse 11 frames contain the timing adjustment information necessary to 12 achieve synchronization. 13

h. If the BSC has chosen to be notified of the start of transmission and 14 reception at the target BTS, when its SDU function and the target 15 BTS have synchronized Abis traffic subchannel, the BTS send an 16 Abis-Traffic Channel Status message to the BSC 17

i. The BSC sends an Extended / General / Universal Handoff Direction 18 Message to the MS to change the cell to the active set. 19

j. The MS acknowledges receipt of the Extended / General / Universal 20 Handoff Direction Message with an MS Ack Order. 21

k. The MS sends reverse traffic channel frames or the traffic channel 22 preamble to the target BTS. 23

l. The MS indicates successful results of processing the Extended / 24 General / Universal Handoff Direction Message by sending a 25 Handoff Completion message. 26

m. The BSC acknowledges receipt of the Handoff Completion Message 27 by sending a BS Ack Order. 28

n. The BSC sends an Abis-BTS-Release message to the source BTS to 29 request that the specified cells be removed from the call. The BSC 30 starts timer Tdrptgtb. 31

o. The source BTS, upon receipt of the Abis-BTS-Release message, 32 deallocates internal resources related to the specified cells. The 33


62

source BTS sends an Abis-Remove message to the SDU function of 1 the BSC and starts timer Tdisconb. 2

p. The SDU function of the BSC replies with an Abis-Remove Ack 3 message and deallocates internal the resources. The target BTS 4 stops timer Tdisconb. 5

q. The target BTS sends an Abis-BTS-Release Ack message to the BSC 6 to acknowledge the removal of the specified cells. The BSC stops 7 timer Tdrptgtb. 8

9


63

5.5 SMS Delivery 1

Delivery of a mobile terminated SMS (SMS-MT) and a mobile originated SMS 2 (SMS-MO) messages on the control channel is accomplished by the exchange of the 3 following messages. 4

Abis-PCH Msg Transfer 5

Abis-PCH Msg Transfer Ack 6

Abis-ACH Msg Transfer. 7

Delivery of a mobile terminated SMS (SMS-MT) and a mobile originated SMS 8 (SMS-MO) on the traffic channel is accomplished by the exchange of the following 9 messages. 10



5.5.1 SMS Delivery on the Paging channel 13 14

5.5.1.1 Abis-PCH Msg Transfer 15

See section 5.1.9. 16 17


When the MSC determines that it needs to deliver an SMS message to a specific idle 19 mobile station, and a Layer 2 acknowledgment notification is required from the MS, the 20 MSC starts timer T3113, sends the ADDS Page message containing a Tag information 21 element to the BSC. MSC waits for the ADDS Page Ack message. 22

When the MSC determines that it needs to deliver an SMS message to a specific idle 23 mobile station, and the MSC does not require a Layer 2 acknowledgment notification, the 24 MSC sends the ADDS Page message, without a Tag information element, to the BSC. 25

When the BSC receives the ADDS Page message, the BSC sends an Abis-PCH Msg 26 Transfer to transfer a Data Burst Message to the BTS. The Data Burst Message contains 27 an SMS message sent from the MSC using the ADDS Page message. If the Tag 28 information element is included in the ADDS Page message, the BSC requires a Layer 2 29 acknowledgement from the MS by setting a Layer 2 Ack Request/Results field to ‘1’. 30 And ARQ fields of the Data Burst Message are also set to values that require the Layer 2 31 Acknowledgement. 32

When the BTS receives the Abis-PCH Msg Transfer message, the BTS sends Data Burst 33 Message on the Paging channel. 34


None. 36

37


64

5.5.1.2 Abis-PCH Msg Transfer Ack 1


3

5.5.1.2.1 Successful Operarion 4

If the Layer 2 acknowledgement is required, that is to say an Abis Ack Notify element 5 contained in the Abis-PCH Msg Transfer message is presented, the BTS sends the 6 Abis-PCH Msg Transfer Ack after the BTS receives an MS Ack Order from the MS. On 7 receipt of the Abis-PCH Msg Transfer Ack, the BSC will wait for A Abis ACH Message 8 Transfer carrying an MS Ack Order from the MS. On receipt of the Abis ACH Message 9 Transfer message the BSC sends a ADDS Page Ack to the MSC. 10

11


None. 13 14

5.5.1.3 Abis-ACH Msg Transfer 15


17


The BTS without L2 termination simply transfers an MS Ack order to the BSC by 19 utilizing an Abis-ACH Msg Transfer, when the BTS receives the MS Ack order. 20

On receipt of the MS Ack Order transferred by the Abis-ACH Msg Transfer, the BSC 21 sends the ADDS Page Ack to the MSC. 22

23


None. 25

26 27

28


65

5.5.2 Call flow example for SMS Delivery on the Paging channel 1 This section provides the call flow description for the delivery of an SMS from the MSC to an idle 2 mobile station on the paging channel. 3 4

5

Figure 5.5.2-1 SMS Delivery on the Paging channel 6

a. When the MSC determines that a point-to-point short message should be sent to an idle 7 MS, the MSC sends an ADDS Page message to the BSC. The ADDS Page message contains the 8 SMS message in its ADDS User Part information element. If the MSC requires an acknowledgment, 9 it will include the Tag element in the ADDS Page message. The MSC also starts timer T3113. 10

b. The BSC sends the Abis-PCH Msg. Transfer that includes a Data 11 Burst message. The Data Burst Message contains the short message 12 in received ADDS Page. 13

c. The BTS transfers the Data Burst message that is included in the 14 Abis-PCH Msg. Transfer message, on a Paging Channel. 15

d. In case that the BTS receives the Abis Ack Notify element included 16 in the Abis-PCH Msg Transfer message, the BTS sends Abis-PCH 17 Msg Transfer Ack after Layer 2 acknowledgement, i.e. receiving an 18 MS Ack Order from the MS. The BTS L2 Termination is set to ‘1’ to 19 indicate that Layer 2 is terminated at the BTS. When the BSC 20 receives the Abis-PCH Msg Transfer Ack and Layer 2 is terminated 21 at the BTS, 22

e. The BSC sends ADDS PAGE Ack to the MSC when the BSC 23 receives Abis-PCH Msg Transfer Ack. 24

MS BTS MSCADDS Page

ADDS Page Ack

BSC

BS

MS Ack Order

Data Burst Message

Abis--PCH Msg Transfer (Data Burst Message)

Abis-ACH Msg Transfer (MS Ack Order)

a

bcd

Time Comment

T3113Abis-PCH Msg Transfer Ack

e


66

f. When the MSC receives the ADDS Page Ack, the MSC stops timer 1 T3113 if the timer was previously started. 2

3 4


67

5.5.3 SMS Delivery on the Access channel 1 2

5.5.3.1 Abis-ACH Msg Transfer 3


5


When the BTS receives the Data Burst Message that contains an SMS message on the 7 Access channel from the MS, the BTS sends Abis-ACH Msg Transfer to transfer the Data 8 Burst Message to the BSC. 9

10

When the MS requires Layer 2 acknowledgement, the BTS sends the MS Ack Order to 11 the MS on the Paging channel. 12

The BSC sends the ADDS Transfer that includes the SMS message to the MSC. 13

14


None 16

17

5.5.3.2 Abis-PCH Msg Transfer 18


20


When the BTS receives the Abis-PCH Msg Transfer that contains the BS Ack Order, the 22 BTS sends the BS Ack Order to the MS on the Paging channel and sends the Abis-PCH 23 Msg Transfer Ack to the BSC. 24

25


None 27

28

5.5.3.3 Abis-PCH Msg Transfer Ack 29

See section 5.1.10 30

31


68


When the BSC receives the Abis-PCH Msg Transfer Ack from the BTS, the BSC knows 2 that the BTS received the Abis-PCH Msg Transfer successfully. A BTS L2 Termination 3 field in the Abis-PCH Msg Transfer Ack is set to ‘0’. 4

5


None 7 8

9


69

5.5.3.5 Call flow example for SMS Delivery on the Access channel 1 2

This section provides the call flow description for the delivery of an SMS from the mobile station to 3 the MSC on the access channel. 4

5 6

Figure 5.5.3.5-1 SMS Delivery on the Access channel 7

a. a. The MS sends a Data Burst Message on the Access 8 Channel to transfer the SMS message. 9

b. The BTS sends the Abis-ACH Msg Transfer message that contains 10 the Data Burst Message received on the Access Channel. 11

When the MS requires Layer 2 acknowledgement, the BTS sends the 12 MS Ack Order to the MS on the Paging channel. 13

c. The BSC sends the ADDS Transfer message to the MSC that 14 contains the Data Burst Message received from the MS in the ADDS 15 User Part element 16

17

18

MS BTS MSC

ADDS Transfer

BSC

BS

Data Burst MessageAbis-ACH Msg Transfer (Data Burst Message)

a

b

c

Time Comment

BS Ack Order


70

5.5.4 SMS Delivery on the Traffic channel to MS 1 This section provides the call flow description for the delivery of an SMS from the MSC to a mobile 2 station operating on the traffic channel. 3

4

Figure 5.5.4-1 SMS Delivery on the Traffic channel to MS 5

a. When the MSC determines that a point-to-point short message should 6 be sent to an idle MS, the MSC sends an ADDS Deliver message to 7 the BSC. The ADDS Deliver message contains the short message in 8 the ADDS User Part information element. 9

b. The BSC sends Abis-IS-2000 FCH Fwd containing the Data Burst 10 Message 11

c. The Data Burst Message is sent on the traffic channel. 12

d. The MS acknowledges the receipt of the Data Burst Message, if it is 13 required. 14

e. The BTS sends Abis-IS-2000 FCH Rvs containing the MS Ack 15 Order. 16

f. The BSC sends ADDS Deliver Ack to acknowledge the ADDS 17 Deliver. 18

19 20

MS BTS MSCADDS Deliver

ADDS Deliver Ack

BSC

BS

MS Ack Order

Data Burst Message

Abis-IS-2000 FCH Fwd(Data Burst Message)

Abis-IS-2000 FCH Rvs(MS Ack Order)

a

bcdef

Time Comment


71

5.5.5 SMS Delivery on the Traffic channel from MS 1 This section provides the call flow description for the delivery of an SMS from a mobile station 2 operating on the traffic channel to the MSC. 3

4

5

Figure 5.5.5-1 SMS Delivery on the Traffic channel from MS 6

a. The MS sends a Data Burst Message on the Access Channel to 7 transfer the SMS message. 8

b. The BTS sends Abis-IS-2000 FCH Rvs containing the Data Burst 9 Message to the BSC. 10

c. The BS sends an ADDS Deliver message to the MSC. The ADDS 11 User Part element contains the SMS message. 12

d. The BSC sends Abis-IS-2000 FCH Fwd message including the BS 13 Ack Order to acknowledge receipt of the Data Burst Message, if it is 14 required. 15

e. The BTS transfer the BS Ack Order. 16

17

18

MS BTS MSC

ADDS Deliver

BSC

BS

BS Ack Order

Data Burst MessageA3-IS-2000 FCH Rvs(Data Burst Message)

A3-IS-2000 FCH Fwd (BS Ack Order)

abcde

Time Comment


72

5.6 Traffic Burst Operation 1

This section describes the messages and procedures used between BSC and BTS to 2 support Traffic Burst Operation. The following messages are used: 3

Abis-Burst Request 4

Abis-Burst Response 5

Abis-Burst Commit 6 7

5.6.1 Abis-Burst Request 8

The Abis-Burst Request message is used by the BSC to request that a BTS reserve a set 9 of radio resources in support of a traffic burst. 10

11


When the BSC determines that a traffic burst is required in support of a particular service 13 instance, it determines the cells needed to support the traffic burst and sends an 14 Abis-Burst Request to the BTS. This message requests that the BTS reserve the 15 indicated radio resources for a traffic burst beginning at a particular time and for a 16 particular duration. This message may also be used to request an extension of an 17 existing traffic burst by specifying the appropriate beginning and duration times. The 18 BSC then starts timer Tbstreqb. 19

Please refer to section 6.1.9, “Abis-Burst Request,” for the format and content of this 20 message. 21

22


If timer Tbstreqb expires, the BSC may choose to resend the Abis-Burst Request 24 message. 25

26

5.6.2 Abis-Burst Response 27

The Abis-Burst Response message is used by the BTS to respond to a request that it 28 reserve radio resources in one or more cells for support of traffic burst. 29

30


When the BTS receives an Abis-Burst Request message, it determines whether it can 32 provide the requested radio resources in support of the traffic burst. If a traffic burst for 33 the same service instance was already committed (and possibly active) at the time the 34 Abis-Burst Request message is received, the BTS shall examine the starting time and 35


73

duration, as well as the set of requested resources to determine if this request extends the 1 traffic burst. The BTS then creates one or more Abis-Burst Response message(s) 2 indicating its ability to support the requested traffic burst for each of the cells included in 3 the Abis-Burst Request message. The BTS starts timer Tbstcomb after each Abis-Burst 4 Response message. The BSC stops timer Tbstreqb when it receives Abis-Burst 5 Response message(s) accounting for all cells included in the Abis-Burst Request 6 message. 7

Please refer to section 6.1.10, “Abis-Burst Response,” for the format and content of this 8 message. 9

10


If timer Tbstcomb expires, the BTS may decommit all radio resources committed for the 12 cell(s) included in this message. 13

14

5.6.3 Abis-Burst Commit 15

The Abis-Burst Commit message is used by the BSC to indicate to the BTS the set of 16 target radio resources that will be used to support a traffic burst. 17

18


When the BSC has gathered traffic burst commitment information from BTSs and has 20 prepared the frame selector(s) to support the traffic burst, it sends an Abis-Burst Commit 21 message to the BTSs to indicate the set of committed target radio resources that will be 22 used to support the traffic burst. 23

When the BTS receives this message, it shall prepare all indicated resources for support 24 of the traffic burst. Any resources that were reserved but are not included in this 25 message may be decommitted by the BTS. This includes bandwidth and burst duration. 26 The BTS stops timer Tbstcomb. 27

Please refer to section 6.1.11, “Abis-Burst Commit,” for the format and content of this 28 message. 29

30


None 32

33

5.6.4 High Speed Packet Data 34

Support of high speed packet data (i.e., speeds greater than 14.4 kbps) may be 35 accomplished through the use of multiple physical channels. These physical channels 36 are supported in the infrastructure using Abis traffic connections during soft/softer 37 handoff. Setup of an Abis connection for a traffic burst is accomplished using 38 Abis-Burst Request, Abis-Burst Response, and Abis-Burst Commit messages. 39


74

Establishment of the Abis connection for the supplemental channel (SCH) is 1 accomplished via the Abis-BTS Setup, Abis-BTS Setup Ack, Abis-Connect and 2 Abis-Connect Ack messages. 3

In this version of this standard, it is assumed that any leg for a supplemental channel will 4 be established on a cell that already supports a leg for the fundamental channel (FCH) or 5 the dedicated control channel (DCCH) for the same mobile station. To minimize the 6 time required to establish a traffic burst, the Abis connection for the SCH is established 7 on the BTS at the transmission of the first data burst. When a leg is established for a 8 SCH, only the terrestrial resources are allocated, i.e., the Abis connection. This involves 9 choosing the traffic circuit to be used and establishing context between the BTS and the 10 BSC/SDU function. Allocation of radio resources for the SCH is made each time that a 11 traffic burst is set up. 12

When the BSC realizes that it is necessary to allocate radio resources for a traffic burst in 13 either the forward or reverse direction or both, it sends an Abis-Burst Request message to 14 each BTS to request reservation of specific radio resources. Each BTS responds with an 15 Abis-Burst Response message to indicate radio resource reservations. Once the BSC has 16 received all expected Abis-Burst Response messages, it sends an Abis-Burst Commit 17 message to each BTS to confirm the traffic burst and the set of radio resources to be used. 18 Each BTS then prepares all indicated cells, connects them to the pre-established Abis 19 connections, and then participates in the burst. This is shown in the example in section 20 5.6.5 and 5.6.6. 21

22 23

24


75

5.6.5 Initial Traffic Burst Example – Abis Connection Not Yet Established 1 The example below describes the support of traffic burst operation when the Abis 2 connection has not yet been established. 3 4

M S BTS M SC Time Comment

a

b

c

d

e

f

g

BSC

h

j

i

k

Abis-BTS Setup

Abis-Connect

Abis-Connect Ack

ESCAM

SCRM (data to be sent)

Abis-BTS Setup Ack

Abis-Burst Request

Abis-Burst Response

Abis-Burst Commit

Layer 2 Ack

Forward and/or reverse traffic burst

optional

optional

Tsetupb

Tconnb

Tbstcomb

Tbstreqb

5

6

Figure 5.6.5-1 Initial Traffic Burst Example 7

a. Either the BSC receives an indication from the MS (via a SCRM 8 message) or from the network (via data being received from the 9 PDSN) that data needs to be sent to/from the MS. The BSC decides a 10 traffic burst on one or more new cells at a BTS is required in support 11 of a service instance in soft/softer handoff. This example assumes 12 that a Fundamental Channel (FCH) or Dedicated Control Channel 13 (DCCH) leg already exists on the selected cell(s) at the BTS. 14

b. The BSC assigns an Abis From ID value and sends an Abis BTS 15 Setup message to the BTS to establish an Abis traffic connection to 16 support a Supplemental Channel (SCH) for the call. This example 17 shows only a single Abis connection being established. The BSC is 18 not required to assign a physical Frame Selector at this time. The 19 BSC starts timer Tsetupb. 20


76

c. The BTS assigns a traffic circuit and optionally a Channel Element 1 ID (CE ID) for each Abis traffic connection and sends an 2 Abis-Connect message to the BSC indicating the Traffic Circuit ID, 3 optional Abis From ID and CE ID to be associated with the specified 4 Abis From ID. The BSC and BTS save the association of CE ID, 5 Traffic Circuit ID, with Cell ID(s). The BSC also saves the Abis 6 From ID value, to be included in subsequent Abis messages to the 7 BTS. The BTS starts timer Tconnb. This is only done at the initial 8 burst. 9

d. The BSC responds with an Abis Connect Ack message to complete 10 the Abis connection. This includes an Abis From ID value assigned 11 by the BSC, which will be included by the BTS in subsequent Abis 12 messages to the BSC. The BTS stops timer Tconnb. 13

e. The BTS sends Abis-BTS Setup Ack messages to the BSC to 14 complete the Abis traffic circuit connection setup procedure for the 15 specified set of cells. This includes an Abis From ID value assigned 16 by the BTS, which will be included by the BSC in subsequent Abis 17 messages to the BTS for this call association. The BSC stops timer 18 Tsetupb. 19

When the BSC has knowledge of resources for SCH in the BTS, the 20 procedure at step f and at step g is not necessary. 21

f. The BSC sends an Abis-Burst Request including the Abis to ID to the 22 BTS to request the reservation of the needed radio resources for the 23 supplemental channel. The BSC starts timer Tbstreqb. Note that the 24 BSC may send an Abis-Burst Request to the BTS at any time after 25 receiving the Abis-BTS Setup message in step c, and that the set of 26 cells may be subset of the cells assigned in step a-e. 27

g. The BTS determines that it can reserve part or all of the requested 28 resources and sends Abis-Burst Response message(s) including Abis 29 From ID to the BSC indicating the resources that have been reserved 30 and committed to the traffic burst, and the cause value for any 31 uncommitted cells. Each reservation includes a physical Channel 32 Element. Note that the physical Channel Element may be allocated 33 any time after step b. The BTS starts timer Tbstcomb. The BSC stops 34 timer Tbstreqb. 35

h. In the Abis-Burst commit message, Walsh codes are used as obtained 36 from the Abis-Burst Response message, but the rate could be 37 downgraded in the Abis-Burst commit message by the BSC. Thus the 38


77

BSC chooses the Walsh code that determines the actual rate for the 1 traffic burst. However, if the BSC chooses a Walsh code other than 2 the one allocated by the BTS, it shall do so only to reduce the burst 3 rate. The new Walsh code in the Burst Commit message shall be 4 derived from the Walsh code in the Burst Response Message. The 5 BTS stops timer Tbstcomb. Note that the BSC may allocate the frame 6 selector any time after step b. Any resources (cells) not included in 7 the Abis-Burst Commit message may be released by the BTS. 8

i. The BSC commands the MS to prepare for the traffic burst via an 9 ESCAM message. 10

j. The MS acknowledges the command from the BSC with a Layer 2 11 Ack. 12

k. The network and mobile station exchange forward and/or reverse 13 traffic burst information for the specified duration, or until the BSC 14 terminates or extends the traffic burst. 15

16

17


78

5.6.6 Subsequent Traffic Burst Example 1

The example below describes the support of traffic burst operation when the Abis 2 connection for the supplemental channel (SCH) has already been established. 3 4

MS BTS MSC Time Comment

a

b

c

d

e

f

g

BSC

ESCAM

SCRM (data to be sent)

Abis-Burst Request

Abis-Burst Response

Abis-Burst Commit

Layer 2 Ack

Forward and/or reverse traffic burst

optional

optionalTbstcomb

Tbstreqb

5

Figure 5.6.6-1 Subsequent Traffic Burst Example 6

a. Either the BSC receives an indication from the MS (via a SCRM 7 message) or from the network (via data being received from the 8 PDSN) that data needs to be sent to/from the MS. 9

When the BSC has knowledge of resources for SCH in the BTS, the 10 procedure at step b and at step c is not necessary. 11

b. The BSC decides a traffic burst is required on one or more cells for 12 which an Abis connection already exists in support of a supplemental 13 channel. The BSC sends an Abis-Burst Request to the BTS to request 14 the reservation of the needed radio resources for the supplemental 15 channel. The BSC starts timer Tbstreqb. 16

c. The BTS determines that it can reserve part of all of the requested 17 resources and sends Abis-Burst Response message(s) to the BSC 18 indicating the resources that have been reserved and committed to the 19 traffic burst, and the cause value for any uncommitted cells. Each 20 reservation includes a physical Channel Element. Note that the 21 physical Channel Element may be allocated any time after step b. The 22 BTS starts timer Tbstcomb. The BSC stops timer Tbstreqb. 23

d. In the Abis-Burst commit message, Walsh codes are used as obtained 24 from the Abis-Burst Response message, but the rate could be 25


79

downgraded in the Abis-Burst commit message by the BSC. Thus the 1 BSC chooses the Walsh code that determines the actual rate for the 2 traffic burst. However, if the BSC chooses a Walsh code other than 3 the one allocated by the BTS, it shall do so only to reduce the burst 4 rate. The new Walsh code in the Burst Commit message shall be 5 derived from the Walsh code in the Burst Response Message.. The 6 BTS stops timer Tbstcomb. Note that the BSC may allocate the frame 7 selector any time after step b. Any resources (cells) not included in 8 the Abis-Burst Commit message may be released by the BTS. 9

e. The BSC commands the MS to prepare for the traffic burst via an 10 ESCAM message. 11

f. The MS acknowledges the command from the BSC with a Layer 2 12 Ack. 13

g. The network and the MS exchange forward and/or reverse traffic 14 burst information for the specified duration, or until the BSC 15 terminates or extends the traffic burst. 16

17


80

5.7 PACA Service 1

PACA queuing processing is performed by following message; 2

Abis-PACA Update 3

4

5.7.1 PACA Updating 5 6

5.7.1.1 Abis-PACA Update 7

The Abis-PACA Update message is used by the BSC to instruct the BTS to update PACA 8 related information. 9

10


The Abis-PACA Update message is sent by the BSC upon receiving a PACA Update 12 message from the MSC with an indication to “Remove MS from the queue”, “Remove 13 MS from the queue and release MS” or “Update Queue Position and Release MS” or if 14 the BSC autonomously decides to do a cancel a PACA call. 15

16


None. 18

19 20 21

22


81

5.7.2 Call flow example for PACA Updating 1

This section describes the call flow associated with PACA updating procedure. 2 3

4

Figure 5.7.2-1 PACA Updating procedure 5

a. When the MSC determines that the PACA control for the BSC is 6 needed, the MSC sends the PACA Update message and starts the 7 timer Tpaca2. 8

b. Upon receipt of the PACA Update message with an indication to 9 “Remove MS from the queue”, “Remove MS from the queue and 10 release MS” or “Update Queue Position and Release MS”, the BSC 11 sends the Abis-PACA Update message to the BTS. In case of 12 “Remove MS from the queue and release MS” or “Update Queue 13 Position and Release MS” the BSC sends a message to the MS via 14 the Abis-IS-2000 FCH Fwd message, and in addition the BSC sends 15 the Abis-PACA Update message to instruct the BTS to perform the 16 desired update action. 17

c. The BSC sends the PACA Update Ack message to the MSC. The 18 MSC stops the timer Tpaca2 upon receipt of the PACA Update Ack 19 message. 20

21 22 23 24 25

26

MS BTS MSC

PACA Update

PACA Update Ack

BSC

BS

Abis-PACA Update

a

b

c

Time Comment

Tpaca2


82

6. Abis Interface Message 1

6.1 Abis Interface Message Formats 2

For Abis interface messages there are a number of information elements that are 3 individually defined in section 7.1. Each information element in a given message is 4 tagged with a reference in section 7.1, a direction indication (i.e., some elements within a 5 message are bi-directional and others are not), and a Required or Optional type (M/O) 6 indicator. 7

The inclusion of information elements in each message is specified as follows: 8

� R - information elements which are required for the message. 9

� O - information elements which are optional for the message. 10

11

6.1.1 Message Body, Coding, and Ordering of Elements 12

For each Abis Interface message there are a number of information elements that are 13 individually defined in section 7.1. Each information element in a given message is 14 tagged with a reference in section 7.1, a direction indication (i.e., some elements within a 15 message are bi-directional and others are not), and a required or optional type. 16 Information elements that are marked as optional carry an additional explanation of when 17 they are used. Some information elements are reused in multiple messages. 18

19

The DIRECTION indication associated with each message element pertains to the use of 20 that particular message element when used with the particular message (i.e., use of the 21 message element may be different in other messages). The format of the DIRECTION 22 indication is as follows: 23

Table 6.1.1-1 Element Flow DIRECTION Indication 24

BTS -> BSC Element flows from BTS to the BSC BSC -> BTS Element flows from the BSC to the BTS

25

The inclusion of information elements in each message is specified as follows: 26

• O - information elements which are optional for the message. The conditions for inclusion of this 27 element are defined in the operation(s) where the message is used and in footnotes associated with the 28 table defining the order of information elements in the message. 29

• R - Required in this version of this specification in the message whenever the message is sent. 30

Information elements that are required for a given message shall be present, and shall 31 appear in the order shown in the message definitions in this chapter. 32

33


83

Information elements that are optional for a given message are included as needed for 1 specific conditions. When included, they shall appear in the order shown in the message 2 definitions in this chapter. 3

4

An information element can very well be required for some messages and optional for 5 other messages. 6

All information elements shall include their Information Element Identifier (IEI) except 7 for the “Message Type” IE. 8

The bitmap tables in the message subsections of 6.1 are patterned after the format for the 9 information elements of section 7.1 and use the following conventions: 10

⇒ Element Name{<# instances>: 11

= Name of information element. 12

Different elements within a message are separated by 13 double lines. 14

Fields within elements are separated by single lines. 15

Octets are renumbered at the beginning of every element. 16

[<values>] = Set of allowed values. 17

} Element Name The number of instances of an element is 1 by default. If 18 the Element Name{<# instances … }Element Name 19 notation is used, the <# instances> notation indicates: 20

n = exactly n occurrences of the element 21

n+ = n or more occurrences of the element 22

1..n = 1 to n inclusive occurrences of the element 23

label {<# instances>: 24

<octet 1> 25

<octet m> 26

} label = Number of instances of the bracketed set of fields where 27 <# instances> notation indicates: 28

n = exactly n occurrences of the field 29

n+ = n or more occurrences of the field 30

1..n = 1 to n inclusive occurrences of the field 31

ssss ssss 32

• • • = Variable length field. 33


84

ssss ssss 1

2

6.1.2 Message Processing Guidelines 3

The following message processing guidelines apply unless overridden by explicit 4 processing directions in other places within this standard. 5

1. If a message is received containing a Message Type value that is not defined for the revision 6 level implemented then the message shall be discarded and ignored. There shall be no change 7 in state or in timers due to receipt of an unknown message. 8

2. If a message is received that contains an information element which is defined for the revision 9 level implemented but contains invalid values in some fields, these fields shall be ignored and 10 the remainder of the information element processed to the extent possible. The message and all 11 other information elements shall be processed to the extent possible. Failure handling may be 12 initiated if call processing cannot continue. See also message processing guidelines 9 and 10 13 below. 14

3. If a message is received that contains an Information Element Identifier which is not defined for 15 the revision level implemented then that element shall be discarded and ignored. The message 16 shall be processed to the extent possible. Failure handling may be initiated if call processing 17 cannot continue. 18

4. If a known but unexpected optional information element is received, that information element 19 shall be ignored. The message and all other information elements shall be processed. 20

5. If a message is received without an expected optional information element the message shall be 21 processed to the extent possible. Failure handling may be initiated if call processing cannot 22 continue. 23

6. No value of an information element that is indicated as “reserved” for the revision level 24 implemented shall be sent. If a valid information element contains a value which is specified 25 as “reserved” or is otherwise not defined in the revision level implemented then this field shall 26 be ignored and the remainder of the information element processed to the extent possible. The 27 message and all other information elements shall be processed to the extent possible. 28

7. Octets and bits designated as “Reserved” or which are undefined for the revision implemented 29 shall be set to zero by a sending entity and ignored by a receiving entity. 30

8. If an element is received containing a field that is larger than expected, i.e., is indicated as 31 having more bits/octets than expected, then the expected bits/octets of that field shall be 32 processed to the extent possible and the additional bits/octets shall be ignored. 33


85

9. If an element is received containing a field that is smaller than expected, i.e., is indicated as 1 having fewer bits/octets than expected, then the length field or other indicator will be considered 2 correct and the bits/octets actually present in the element shall be processed to the extent 3 possible. Failure handling may be initiated if call processing cannot continue. 4

5

6.1.3 Message Definition Guidelines 6

1. New messages shall have a Message Type that was never previously used. 7

2. Information Element Identifiers may be reused in future revisions only when: 8

� The old use of the element identifier is not used in the new revision, and 9 � The new use of the element identifier is used only in new messages that were 10

not defined in previous revisions. 11 � The old use of the element identifier shall be supported within the context of 12

the old messages in which it was used. 13

3. Defined valid values of Information Elements may be changed in future 14 revisions. The new version shall define the error handling when previously 15 valid values are received. 16

4. Octets and bits which are undefined or which are defined as reserved may be 17 used in future revisions. 18

5. New Information Elements in a message shall be defined after all previously 19 defined Information Elements. 20

6. All new Information Elements shall be defined with a length field. 21

7. New information may be added to the end of an existing Information Element, 22 provided that the Information Element is defined with a length field. 23

24

25

26


86

6.2 Abis interface messages 1

2

6.2.1 Abis-ACH Msg Transfer 3

This Abis interface message is sent from the BTS to the BSC to notify the BSC of the 4 reception of the contained message or Layer 2 acknowledgment on the specified access 5 channel. 6

Information Element Section Reference

Element Direction Type

Message Type 7.2 BTS -> BSC R Correlation ID 7.3 BTS -> BSC O Mobile Identity (IMSI) 7.4 BTS -> BSC O Mobile Identity (ESN) 7.4 BTS -> BSC O Cell Identifier 7.5 BTS -> BSC O

a

BTS L2 Termination 7.30 BTS -> BSC O Air Interface Message 7.6 BTS -> BSC O CDMA Serving One Way Delay 7.24 BTS -> BSC R Authentication Challenge Parameter (RAND) 7.32 BTS -> BSC O

a. This element indicates the cell at the BTS on whose access channel the 7 air-interface message or Layer 2 acknowledgment was received. 8

9

The following table shows the bitmap layout for the Abis-ACH Msg Transfer message: 10 7 6 5 4 3 2 1 0 Octet

⇒⇒⇒⇒ Message Type = [8EH] 1

⇒⇒⇒⇒ Correlation ID: A3/A7 Element Identifier = [13H] 1

Length = [04H] 2 (MSB) 3

Correlation Value = <any value> 4 5

(LSB) 6

⇒⇒⇒⇒ Mobile Identity (IMSI): A1 Element Identifier = [0DH] 1

Length = [06H-08H] (10-15 digits) 2 Identity Digit 1 = [0H-9H] (BCD) Odd/even

Indicator = [1,0]

Type of Identity = [110] (IMSI)

3

Identity Digit 3 = [0H-9H] (BCD) Identity Digit 2 = [0H-9H] (BCD) 4


87

• • • • • •

Identity Digit N+1 = [0H-9H] (BCD) Identity Digit N = [0H-9H] (BCD) n = [1111] (if even number of digits) Identity Digit N+2 = [0H-9H] (BCD) n+1

⇒⇒⇒⇒ Mobile Identity (ESN): A1 Element Identifier = [0DH] 1

Length = [05H] 2 Identity Digit 1 = [0000] Odd/even

Indicator = [0]

Type of Identity = [101] (ESN)

3

(MSB) 4 ESN = <any value> 5

6 (LSB) 7

⇒⇒⇒⇒ Cell Identifier: A1 Element Identifier = [05H] 1

Length = [03H] 2 Cell Identification Discriminator = [02H] 3

(MSB) Cell = [001H-FFFH] 4 (LSB) Sector = [0H-FH] (0H = Omni) 5

⇒ BTS L2 Termination: Abis Element Identifier = [73H] 1

Length = [01H] 2

Reserved = [0000 000] BTS L2

Termination =

[0/1]

3

⇒ Air Interface Message: Abis Element Identifier = [21H] 1

Length = <variable> 2 TIA/EIA-IS-2000 Message Type = <00H to FFH> 3

Air Interface Message Length = <variable> 4 (MSB) 5

Air Interface Message = <any value> … (LSB) k

⇒⇒⇒⇒ CDMA Serving One Way Delay: A1 Element Identifier = [0CH] 1




88

(MSB) CDMA Serving One Way Delay = [0000H-FFFFH] (x100ns) 6 (LSB) 7

⇒⇒⇒⇒ Authentication Challenge Parameter: A1 Element Identifier = [41H] 1

Length 2 Reserved Random Number Type 3

(MSB) 4 RAND Value 5-m

(LSB) m+1

1


89

6.2.2 UNUSED SECTION 1 2

6.2.3 Abis-PCH Msg Transfer 3 4

This Abis interface message is sent from the BSC to the BTS to request the sending of the 5 contained message on the specified paging channels to a mobile station. 6



Message Type 7.2 BSC -> BTS R Correlation ID 7.3 BSC -> BTS O

a

Mobile Identity (IMSI) 7.4 BSC -> BTS Od

Mobile Identity (ESN) 7.4 BSC -> BTS O Cell Identifier List 7.13 BSC -> BTS O

b

Air Interface Message 7.6 BSC -> BTS O Layer 2 Ack Request/Results 7.8 BSC -> BTS O

c

Abis Ack Notify 7.34 BSC -> BTS Oe

a. If this element is included in this message, the value shall be returned in the 7 Abis-PCH Msg Transfer Ack message. 8

b. This element indicates the cells at the BTS on whose paging channel(s) the 9 air-interface message is to be sent. 10

c. This element is included if the BSC wants a Layer 2 acknowledgment from 11 the MS. 12

d. Either IMSI or ESN, but not both is included. (Only one instance of Mobile 13 ID should be allowed) 14

e. The BSC includes this element in this message when it wants to be 15 informed that a layer 2 ack was received from the MS. The BTS will use the 16 Abis-PCH Msg Transfer Ack message to notify the BSC that the layer 2 ack 17 was received. This element should not be included if the Abis Ack 18 Requested IE is absent. 19

20

21


90

The following table shows the bitmap layout for the Abis-PCH Msg Transfer 1 message: 2

7 6 5 4 3 2 1 0 Octet

⇒⇒⇒⇒ Message Type = [8CH] 1




(LSB) 6



Indicator = [1,0]


3


• • • • • •




Indicator = [0]


3


6 (LSB) 7

⇒ Cell Identifier List: A1 Element Identifier = [1AH] 1

Length = <variable> 2 Cell Identification Discriminator = [02H] 3

Cell Identification {1+: (MSB) Cell = [001H-FFFH] j

(LSB) Sector = [0H-FH] (0H = Omni) j+1

} Cell Identification


91

⇒ Air Interface Message: Abis Element Identifier = [21H] 1

Length = <variable> 2 TIA/EIA-IS-2000 Message Type = <00H to FFH> 3

Air Interface Message Length = <variable> 4 (MSB) 5

Air Interface Message = <any value> … (LSB) k

⇒ Layer 2 Ack Request/Results: Abis Element Identifier = [23H] 1

Length = [01H] 2 Reserved = [0000 000] Layer 2

Ack = [0/1]

3

⇒⇒⇒⇒ Abis Ack Notify: Abis Element Identifier = [75H] 1

Length = [00H] 2 1

2


92

6.2.4 Abis-PCH Msg Transfer Ack 1

This Abis interface message is sent from the BTS to the BSC to report the results of 2 sending an air interface message on the specified paging when a layer 2 acknowledgment 3 had been requested by the BSC. 4



Message Type 7.2 BTS -> BSC R Correlation ID 7.3 BTS -> BSC O

a

Cause 7.9 BTS -> BSC Ob

BTS L2 Termination 7.30 BTS -> BSC O

a. This element is included if the Abis-PCH Msg Transfer contained this element. 5 It contains the value received on that message. 6

b. Inclusion of this element indicates a failure to send the paging channel message 7 as requested in the Abis-PCH Msg Transfer message. Allowable cause values: 8 OAM&P intervention, Equipment failure, SMS Message too long for delivery 9 on the paging channel. 10

11

The following table shows the bitmap layout for the Abis-PCH Msg Transfer Ack 12 message: 13

7 6 5 4 3 2 1 0 Octet

⇒⇒⇒⇒ Message Type = [8DH] 1




(LSB) 6

⇒⇒⇒⇒ Cause: A1 Element Identifier = [04H] 1

Length = [01H] 2 ext = [0] Cause Value =

[07H (OAM&P intervention), 20H (equipment failure), 71H (SMS Message too long for delivery on the paging channel)]

3


93

⇒ BTS L2 Termination: Abis Element Identifier = [73H] 1

Length = [01H] 2

Reserved = [0000 000] BTS L2

Terminatio

n =

[0/1]

3

1


94

1

6.2.5 Abis-BTS Setup 2 3

This Abis interface message is sent from the BSC to the BTS in order to request the BTS 4 to assign radio resource, the attributes of which are defined within the message. 5


Element Direction

Type

Message Type 7.2 BSC -> BTS R Call Connection Reference 7.10 BSC -> BTS R Band Class 7.11 BSC -> BTS O Privacy Info 7.12 BSC -> BTS O SDU-ID 7.14 BSC -> BTS O Mobile Identity (IMSI) 7.4 BSC -> BTS O Mobile Identity (ESN) 7.4 BSC -> BTS O Physical Channel Info 7.15 BSC -> BTS O Service Option 7.17 BSC -> BTS Og PACA Timestamp 7.18 BSC -> BTS Oa Quality of Service Parameters 7.19 BSC -> BTS Ob Abis Connect Information 7.20 BSC -> BTS Oc, e Abis Originating ID 7.21 BSC -> BTS Od CDMA Serving One Way Delay 7.24 BSC -> BTS R CDMA Target One Way Delay 7.30 BSC -> BTS O Walsh Code Assignment Request 7.31 BSC -> BTS O f

a. This element may be present only when the call is eligible for PACA service. 6

b. This element may be only used for packet data calls. In this version of this 7 standard, this element is used to carry a Packet Priority field coded on 4 bits. 8 Values ‘1110’ and ‘1111’ are reserved. 9

c. This element may be used to indicate a code channel that is allocated by the BSC. 10 It is assumed that the Cell Info Record is used and 0 fills the rest of the fields. 11

d. This element is optionally included by the BSC. If included, the value shall be 12 saved and used by the BTS in subsequent Abis message for this call association. 13 14

e. If the physical channel type is SCH, then the Extended Handoff Direction 15 Parameters Field Length shall be set to ‘0’ and the following fields shall be 16


95

ignored in the Cell Information Record: QOF_Mask, PWR_Comb_Ind, Pilot_PN, 1 Code Channel. 2

f. This element is included when the BSC requests the BTS for assignment of the 3 Walsh code. If this element is included, Code Channel field of the Abis Connect 4 Information IE is invalid. 5

g. The Service option is set to the service option received in the Origination or 6 Paging Response message from MS. 7

8

9


96

The following table shows the bitmap layout for the Abis-BTS Setup message: 1 7 6 5 4 3 2 1 0 Octet

⇒⇒⇒⇒ Message Type = [80H] 1

⇒⇒⇒⇒ Call Connection Reference: A1 Element Identifier = [3FH] 1

Length = [08H] 2 (MSB) Market ID = <any value> 3

(LSB) 4 (MSB) Generating Entity ID = <any value> 5

(LSB) 6 (MSB) 7

Call Connection Reference = <any value> 8 9

(LSB) 10

⇒⇒⇒⇒ Band Class: A1 Element Identifier = [5DH] 1

Length = [01H] 2 Reserved = [000] Band Class = [ 00001 (PCS)

00010 (TACS) 00011 (JTACS)

00100 (Korean PCS) 00101 (NMT-450) 00110 (IMT-2000)]

3

⇒⇒⇒⇒ Privacy Info: A3/A7 Element Identifier = [1DH] 1

Length = <variable> 2

Privacy Mask Information {1+: Reserved

= [0] Privacy Mask Type = [00001,00010]

(public, private) Status = [0,1]

Available = [0,1]

j

Privacy Mask Length = <variable> j+1 (MSB) Privacy Mask = <any value> j+2

• • • • • • (LSB) k

} Privacy Mask Information

⇒⇒⇒⇒ SDU ID: A3/A7 Element Identifier = [4CH] 1

Length = <variable> 2 (MSB) SDU ID = <any value> 3

• • • • • • (LSB) m



97


Indicator = [1,0]


3


• • • • • •




Indicator = [0]


3


6 (LSB) 7

⇒⇒⇒⇒ Physical Channel Info: A3/A7 Element Identifier = [07H] 1

Length =[05H] 2 Frame Offset = [00H – FFH] 3

A3 Traffic Channel Protocol Stack = [001]

Pilot Gating Rate = [00, 01, 10]

ARFCN (high part) = [000-111]

4

ARFCN (low part) = [00H-FFH] 5 Count of Physical Channels = [01H-02H] 6

Reserved = [0000] OTD=[0,1]

Count of Physical Channels = [001 – 010]

6

Physical Channel 2 = 0H – N/A,

1H – FCH, 2H – SCH,

3H – DCCH

Physical Channel 1 = 0H – IS-95, 1H – FCH, 2H – SCH,

3H – DCCH

7

⇒⇒⇒⇒ Service Option: A1 Element Identifier = [03H] 1

(MSB) Service Option 2 = [0000H - XXXXH]

(LSB) 3

⇒⇒⇒⇒ PACA Timestamp: A1 Element Identifier = [4EH] 1



98

PACA Queuing Time = <any value> 4 5

(LSB) 6

⇒⇒⇒⇒ Quality of Service Parameters: A1 Element Identifier = [07H] 1

Length = [01H] 2 Reserved = [0000] Packet Priority = [0000 – 1101] 3

⇒⇒⇒⇒ Abis Connect Information{1+: A3/A7 Element Identifier = [1BH] 1


Reserved = [000] Physical Channel Type = [0H - IS-95 Fundamental Channel, 1H – Fundamental Channel (FCH), 2H – Supplemental Channel (SCH),

3H – Dedicated Control Channel(DCCH)],

New A3 Indicator = [0,1]

(exist,new)

3

Length of Cell Info Record = <variable> 4

Cell Info Record {1+: Cell Identification Discriminator = [02H] j

(MSB) Cell = [001H-FFFH] j+1 (LSB) Sector = [0H-FH] (0H = Omni) j+2

Reserved = [000] QoF Mask = [00, 01, 10, 11]

New Cell

Indicator = [0,1]

(old, new)

PWR_Comb_Ind

= [0,1] (no,yes)

(MSB) k

Pilot_PN = <any value> (LSB) k+1 Code Channel = [00H - FFH] k+2

} Cell Info Record Length of Traffic Circuit ID = [05H] 1

Traffic Circuit ID {1: Length of Traffic Circuit Identifier = [02H] 2

(MSB) Traffic Circuit Identifier = <any value> 3

(LSB) 4 Length of Traffic Connection Identifier = [01H] 5

Traffic Connection Identifier = [00H-FFH] (AAL2 CID)

6

} Traffic Circuit ID Extended Handoff Direction Parameters Field Length = [09H] p


99

Extended Handoff Direction Parameters {1+: Search Window A Size (Srch_Win_A) =

[0H-FH] Search Window N Size (Srch_Win_N) =

[0H-FH] p+1

Search Window R Size (Srch_Win_R) = [0H-FH]

Add Pilot Threshold (T_Add) high order = [0H-FH]

p+2

T_Add (low order) = [00-11]

Drop Pilot Threshold (T_Drop) = [000000-111111] p+3

Compare Threshold (T_Comp) = [0H-FH]

Drop Timer Value (T_TDrop) = [0H-FH]

p+4

Neighbor Max Age (Nghbor_Max_AGE) = [0H-FH]

Reserved = [0000] p+5

Reserved = [00] SOFT_SLOPE = [00 0000 - 11 1111] p+6 Reserved = [00] ADD_INTERCEPT = [00 0000 - 11 1111] p+7 Reserved = [00] DROP_INTERCEPT = [00 0000 - 11 1111] p+8

Target BS P_REV = [00H – FFH] p+9

} Extended Handoff Direction Parameters Length of Channel Element ID = <variable> q

(MSB) Channel Element ID = <any value> q+1 • • • • • •

(LSB) r

Length of A3 Originating ID = [02H] r+1 (MSB) A3 Originating ID = <any value> r+2

(LSB) r+3

Length of A7 Destination ID = [02H] r+4 (MSB) A7 Destination ID = <any value> r+5

(LSB) r+6

}Abis Connect Information

⇒⇒⇒⇒ Abis Originating ID: Abis Element Identifier = [71H] 1

Length of Abis Originating ID = [02H] 1 (MSB) Abis Originating ID = <any value> 2

(LSB) 3




(MSB) CDMA Serving One Way Delay = [0000H-FFFFH] (x100ns) 6


100

(LSB) 7

⇒⇒⇒⇒ CDMA Target One Way Delay: Abis Element Identifier = [0BH] 1

Length = [02H] 2 CDMA Target One Way Delay (high part) 3 CDMA Target One Way Delay (low part) 4

⇒⇒⇒⇒ Walsh Code Assignment Request: Abis Element Identifier = [74H] 1

Length = [00H] 2

1 2


101


This message is sent from BTS to BSC to acknowledge the Abis-BTS Setup. 2

3 Information Element Section

Reference Element Direction

Type

Message Type 7.2 BTS -> BSC R Call Connection Reference 7.10 BTS -> BSC R Abis Connect Information 7.20 BTS -> BSC O Abis Originating ID 7.21 BTS -> BSC Oa Abis Destination ID 7.22 BTS -> BSC Ob Cause 7.9 BTS -> BSC Oc

a. This element is optionally included by the BTS. If included, the value 4 shall be saved and used by the BSC in subsequent Abis message for 5 this call association. 6

b. This element is required if an Abis Originating ID value was included 7 in the corresponding Abis-BTS Setup message 8

c. Inclusion of this element indicates failure of the Abis-BTS Setup 9 message. Allowable cause values: No radio resource available. 10

11 12


102

The following table shows the bitmap layout for the Abis-BTS Setup Ack message: 1

2 7 6 5 4 3 2 1 0 Octet





(LSB) 6 (MSB) 7


(LSB) 10

⇒⇒⇒⇒ Abis Connect Information{1+: A3/A7 Element Identifier = [1BH] 1


Reserved = [000] Physical Channel Type = [0H - IS-95 Fundamental Channel, 1H – Fundamental Channel (FCH), 2H – Supplemental Channel (SCH),

3H – Dedicated Control Channel(DCCH)],


(exist,new)

3


Cell Info Record {1+: Cell Identification Discriminator = [02H] j

(MSB) Cell = [001H-FFFH] j+1 (LSB) Sector = [0H-FH] (0H = Omni) j+2

Reserved = [000] QoF Mask = [00, 01, 10, 11]

New Cell

Indicator = [0,1]

(old, new)

PWR_Comb_Ind

= [0,1] (no,yes)

(MSB) k


} Cell Info Record Length of Traffic Circuit ID = [05H] 1

Traffic Circuit ID {1: Length of Traffic Circuit Identifier = [02H] 2


103

(MSB) Traffic Circuit Identifier = <any value> 3

(LSB) 4 Length of Traffic Connection Identifier = [01H] 5

Traffic Connection Identifier = [00H-FFH] (AAL2 CID)

6

} Traffic Circuit ID Extended Handoff Direction Parameters Field Length = [09H] p

Extended Handoff Direction Parameters {1+: Search Window A Size (Srch_Win_A) =

[0H-FH] Search Window N Size (Srch_Win_N) =

[0H-FH] p+1



p+2





p+4





} Extended Handoff Direction Parameters Length of Channel Element ID = <variable> q


(LSB) r

Length of A3 Originating ID = [02H] r+1 (MSB) A3 Originating ID = <any value> r+2

(LSB) r+3

Length of A7 Destination ID = [02H] r+4 (MSB) A7 Destination ID = <any value> r+5

(LSB) r+6

}Abis Connect Information

⇒⇒⇒⇒ Abis Originating ID: Abis Element Identifier = [71H] 1

Length of Abis Originating ID = [02H] 2


104

(MSB) Abis Originating ID = <any value> 3 (LSB) 4

⇒⇒⇒⇒ Abis Destination ID: Abis Element Identifier = [72H] 1

Length of Abis Destination ID = [02H] 2 (MSB) Abis Destination ID = <any value> 3

(LSB) 4

⇒⇒⇒⇒ Cause: Abis Element Identifier = [04H] 1

Length = [01H] 2 Ext = [0] Cause Value = [21H (No radio resource available)] 3

1 2


105

6.2.7 Abis-BTS Release 1

This message is sent from BSC to BTS to instruct the BTS to release the associated 2 dedicated resource. 3

4


Element Direction

Type

Message Type 7.2 BSC -> BTS R Call Connection Reference 7.10 BSC -> BTS R Cell Identifier List 7.5 BSC -> BTS O Correlation ID 7.3 BSC -> BTS O

5

The following table shows the bitmap layout for the Abis-BTS Release message: 6 7 6 5 4 3 2 1 0 Octet





(LSB) 6 (MSB) 7


(LSB) 10

⇒⇒⇒⇒ Cell Identifier List: A1 Element Identifier = [1AH] 1


Cell Identification Discriminator = [02H] 3

Cell Identification {1+:

(MSB) Cell = [001H-FFFH] j




Length = [04H] 2

(MSB) 3

Correlation Value = <any value> 4


106

5

(LSB) 6 1

2


107

6.2.8 Abis-BTS Release Ack 1

This message is sent from the BSC to the BTS to acknowledge the Abis-BTS Release. 2

3


Element Direction

Type

Message Type 7.2 BSC -> BTS R Call Connection Reference 7.10 BSC -> BTS R Correlation ID 7.3 BSC -> BTS O

4

The following table shows the bitmap layout for the Abis-BTS Release Request Ack message: 5

7 6 5 4 3 2 1 0 Octet





(LSB) 6 (MSB) 7


(LSB) 10


Length = [04H] 2

(MSB) 3

Correlation Value = <any value> 4

5

(LSB) 6 6

7

8


108

6.2.9 Abis-Burst Request 1

This Abis interface message is sent from the BSC to the BTS to request the reservation of 2 resources in support of a traffic burst. 3


Reference Element Direction Type

Message Type 7.2 BSC -> BTS R Call Connection Reference 7.10 BSC -> BTS O Band Class 7.11 BSC -> BTS O Downlink Radio Environment 7.23 BSC -> BTS O CDMA Serving One Way Delay 7.24 BSC -> BTS O Privacy Info 7.12 BSC -> BTS O Correlation ID 7.3 BSC -> BTS O

f

SDU ID 7.14 BSC -> BTS Oa

Mobile Identity (IMSI) 7.4 BSC -> BTS Ob

Mobile Identity (ESN) 7.4 BSC -> BTS Ob

Cell Identifier List 7.5 BSC -> BTS Oc

Forward Burst Radio Info 7.25 BSC -> BTS Od

Reverse Burst Radio Info 7.26 BSC -> BTS Oe

Abis Destination ID 7.22 BSC -> BTS Og

a. Optionally included by the BSC. If included, the value shall be saved and 5 used by the target BS on Abis signaling messages. 6

b. This element may be included for OA&M purposes. 7

c. The list of cell identifiers shall be assumed by the target BTS to be in priority 8 order with the highest priority cell listed first. 9

d. This element is only included when forward link radio resources are to be 10 allocated to the burst. 11

e. This element is only included when reverse link radio resources are to be 12 allocated to the burst. 13

f. If this element is included in this message, its value shall be returned in the 14 Abis-Burst Response message and used in the Abis-Burst Commit message. 15


109

g. This element is required if an Abis Origination ID value was included in an 1 Abis-BTS Setup Ack message previously received from the BTS for this call 2 association. 3

The following table shows the bitmap layout for the Abis-Burst Request message: 4

7 6 5 4 3 2 1 0 Octet





(LSB) 6 (MSB) 7


(LSB) 10

⇒⇒⇒⇒ Band Class: A1 Element Identifier = [5DH] 1

Length = [01H] 2 Reserved = [000] Band Class = [00001] (PCS) 3

⇒⇒⇒⇒ Downlink Radio Environment: A1 Element Identifier = [29H] 1

Length = <variable> 2 Number of Cells = <variable> 3

Cell Identification Discriminator = [02H] 4

Downlink Radio Environment {1+: (MSB) Cell = [001H-FFFH] j

(LSB) Sector = [0H-FH] (0H = Omni) j+1 Reserved = [00] Downlink Signal Strength Raw = [000000] (ignored) k

(MSB) CDMA Target One Way Delay k+1

(LSB) k+2

} Downlink Radio Environment


Length = [08H] 2 Cell Identification Discriminator = [ 02H] 3


(MSB) CDMA Serving One Way Delay = [0000H-FFFFH] (x100ns) 6


110

(LSB) 7

⇒⇒⇒⇒ Privacy Info: A3/A7 Element Identifier = [1DH] 1


Privacy Mask Information {1+: Reserved

= [0] Privacy Mask Type = [00001,00010]

(public, private) Status = [0,1]

Available = [0,1]

j

Privacy Mask Length = <variable> j+1 (MSB) Privacy Mask = <any value> j+2

• • • • • • (LSB) k

} Privacy Mask Information




(LSB) 6


Length = [01H to 06H] 2 (MSB) SDU ID = <any value> 3

• • • • • • (LSB) M



Indicator = [1,0]


3


• • • • • •

Identity Digit N+1 = [0H-9H] (BCD) Identity Digit N = [0H-9H] (BCD) N = [1111] (if even number of digits) Identity Digit N+2 = [0H-9H] (BCD) n+1



Indicator = [0]


3

(MSB) 4


111

ESN = <any value> 5 6

(LSB) 7

⇒⇒⇒⇒ Cell Identifier List: A1 Element Identifier = [1AH] 1


Cell Identification{1+: (MSB) Cell = [001H-FFFH] j



⇒⇒⇒⇒ Forward Burst Radio Info: A3/A7 Element Identifier = [11H] 1

Length = [06H] 2 Coding Indicator

= [00, 01] Reserved

= [0] QOF Mask = [00 – 11]

Forward Code Channel Index (high part)

= [000 – 111]

3

Forward Code Channel Index (low part) = [00H – FFH] 4 Pilot PN Code (low part) = [00H – FFH] 5

Pilot PN Code (high

part) [0,1]

Reserved = [000]

Forward Supplemental Channel Rate = [0000 – 1111]

6

Reserved = [000]

Forward Supplemental Channel Start Time = [0 0000 – 1 1111]

7

Reserved = [0]

Start Time Unit = [000 – 111]

Forward Supplemental Channel Duration = [0000 – 1111]

8

⇒⇒⇒⇒ Reverse Burst Radio Info: A3/A7 Element Identifier = [12H] 1


= [00, 01] Reserved = [00 0000] 3

Reserved = [0000]

Reverse Supplemental Channel Rate = [0000 – 1111]

4

Reverse Supplemental Channel Start Time = [00H – FFH] 5 Reserved

= [0] Start Time Unit = [000 – 111]

Reverse Supplemental Channel Duration = [0000 – 1111]

6




112

(LSB) 4

1


113

6.2.10 Abis-Burst Response 1

This Abis interface message is sent from the BTS to the BSC to respond to a request for 2 reservation of resources to support a traffic burst. Note that one or more Abis-Burst 3 Response messages may be used to respond to a single Abis-Burst Request message. A 4 result (committed or uncommitted) shall be provided for all cells in the Abis-Burst 5 Request message. Each Abis-Burst Response message includes at most one committed 6 cell. 7

8 9 Information Element Section


Message Type 7.2 BTS -> BSC R Call Connection Reference 7.10 BTS -> BSC O Correlation ID 7.3 BTS -> BSC O

a

Cell Identifier List (Committed) 7.5 BTS -> BSC Od

Cell Identifier List (Uncommitted) 7.5 BTS -> BSC Oe

Forward Burst Radio Info 7.25 BTS -> BSC Ob

Reverse Burst Radio Info 7.26 BTS -> BSC Oc

Abis Destination ID 7.22 BTS -> BSC Of

a. If this element was included in the Abis-Burst Request message, the 10 value shall be returned in this message. 11

b. This element is only included when this message includes 12 information about forward link radio resources that have been 13 reserved at the cell indicated in the Cell Identifier List (Committed) 14 element. 15

c. This element is only included when this message includes 16 information about reverse link radio resources that have been 17 reserved at the cell indicated in the Cell Identifier List (Committed) 18 element. 19

d. This element is only included when this message includes 20 information about a cell with radio resources reserved for the forward 21 and/or reverse burst indicated in the Forward and/or Reverse Burst 22 Radio Info element. 23


114

e. This element is only included when this message includes one or 1 more requested cells that are not being reserved. The allowable 2 cause values are: OAM&P intervention, Equipment failure, No radio 3 resource available, BS not equipped, Ciphering algorithm not 4 supported, Private Long Code not available or not supported, 5 Requested MUX option or rates not available, Requested privacy 6 configuration not available. 7

f. This element is required if an Abis Origination ID value was included 8 in an Abis-BTS Setup message previously received from the BSC for 9 this call association. 10

11


115

The following table shows the bitmap layout for the Abis-Burst Response message: 1

7 6 5 4 3 2 1 0 Octet





(LSB) 6 (MSB) 7


(LSB) 10




(LSB) 6

⇒⇒⇒⇒ Cell Identifier List (committed): A1 Element Identifier = [1AH] 1





⇒⇒⇒⇒ Cell Identifier List (uncommitted): A1 Element Identifier = [1AH] 1


-- Continued on next page -- 2


116

1 -- Continued from previous page --






= [00, 01] Reserved

= [0] QOF Mask = [00 – 11]


= [000 – 111]

3


Pilot PN Code (high

part) [0,1]

Reserved = [000]


6

Reserved = [000]


7

Reserved = [0]



8



= [00, 01] Reserved = [00 0000] 3

Reserved = [0000]


4


= [0] Start Time Unit = [000 – 111]


6


Length of Abis Destination = [02H] 2 (MSB) Abis Destination ID = <any value> 3

(LSB) 4 2


117

1

6.2.11 Abis-Burst Commit 2

This Abis interface message is sent from the BSC to the BTS to commit a set of resources 3 that had been reserved to support a traffic burst. 4



Message Type 7.2 BSC -> BTS R Call Connection Reference 7.10 BSC -> BTS O Correlation ID 7.3 BSC -> BTS O

a

Cell Identifier List (Forward) 7.5 BSC -> BTS Ob Cell Identifier List (Reverse) 7.5 BSC -> BTS Ob Forward Burst Radio Info 7.25 BSC -> BTS Oc, h Reverse Burst Radio Info 7.26 BSC -> BTS Od, h IS-2000 Forward Power Control Mode 7.27 BSC -> BTS Oe IS-2000 FPC Gain Ratio Info 7.28 BSC -> BTS Of Abis Destination ID 7.22 BSC -> BTS O

g

a. Optionally included by the BSC. If included, the value shall be 6 saved and used by the target BTS on Abis signaling messages. 7

b. The length field of this element shall be set to ‘0’ if no resources are 8 to be allocated in the indicated direction. 9

c. This element is only included when forward link radio resources are 10 to be allocated to the burst. 11

d. This element is only included when reverse link radio resources are 12 to be allocated to the burst. 13

e. This element shall be included when supporting a secondary power 14 control sub-channel. It provides information used for forward gain 15 equalization for the SCH. 16

f. This element shall be included when supporting a secondary power 17 control sub-channel for the SCH. The FPC_MODE value shall go 18 into effect at the earlier of the burst start times indicated in the 19 Forward Burst Radio Info and/or Reverse Burst Radio Info element. 20


118

g. This element is required if an Abis Originating ID value was included 1 in an Abis BTS Setup Ack message previously received from the 2 BTS for this call association. 3

h. Walsh code in this IE is used as obtained from the Abis-Burst 4 Response message, but the rate could be downgraded in this message. 5

6

Note: In the Abis-Burst commit message, Walsh codes are used as 7 obtained from the Abis-Burst Response message, but the rate could 8 be downgraded in the Abis-Burst commit message by the BSC. Thus 9 the BSC chooses the Walsh code that determines the actual rate for 10 the traffic burst. However, if the BSC chooses a Walsh code other 11 than the one allocated by the BTS, it shall do so only to reduce the 12 burst rate. The new Walsh code in the Burst Commit message shall 13 be derived from the Walsh code in the Burst Response Message. 14

15


119

The following table shows the bitmap layout for the Abis-Burst Commit message: 1

7 6 5 4 3 2 1 0 Octet





(LSB) 6 (MSB) 7


(LSB) 10




(LSB) 6

⇒⇒⇒⇒ Cell Identifier List (Forward): A1 Element Identifier = [1AH] 1





⇒⇒⇒⇒ Cell Identifier List (Reverse): A1 Element Identifier = [1AH] 1




120







= [00, 01] Reserved

= [0] QOF Mask = [00 – 11]


= [000 – 111]

3


Pilot PN Code (high

part) [0,1]

Reserved = [000]


6

Reserved = [000]


7

Reserved = [0]



8



= [00, 01] Reserved = [00 0000] 3

Reserved = [0000]


4


= [0] Start Time Unit = [000 – 111]


6

⇒⇒⇒⇒ IS-2000 Forward Power Control Mode: A3/A7 Element Identifier = [14H] 1

Length = [02H] 2 Reserved = [0000 0] FPC_MODE = [000 – 011] 3

ACTION_TIME = [00H] (ignored) 4

⇒⇒⇒⇒ IS-2000 FPC Gain Ratio Info: A3/A7 Element Identifier = [15H] 1

Length = [08H] 2 Initial Gain Ratio = [00H – FFH] 3


121

Reserved =

[0]

Gain Adjust Step Size = [0H – FH] Count of Gain Ratio Pairs = [011]

4

Min Gain Ratio 1 = [00H – FFH] 5

Max Gain Ratio 1 = [00H – FFH] 6

Min Gain Ratio 2 = [00H – FFH] 7

Max Gain Ratio 2 = [00H – FFH] 8

Min Gain Ratio 3 = [00H – FFH] 9 Max Gain Ratio 3 = [00H – FFH] 10



(LSB) 4 1 2

3


122


2

This message uses the same format as the A3-Connect message modified to include 3 “Physical Channel Info” IE as shown below. 4


Element Direction

Type

Message Type II 6.2.2.5 BTS -> SDU R Call Connection Reference 6.2.2.98 BTS -> SDU R Correlation ID 6.2.2.108 BTS -> SDU Oa SDU ID 6.2.2.91 BTS -> SDU Ob A3 Connect Information 6.2.2.144 BTS -> SDU Rc,d Physical Channel Info 6.2.2.14 BTS -> SDU R

a. If this element is included in this message, it shall be returned in the 5 A3-Connect Ack message. 6

b. If this element was included in the A7-Handoff Request message, it is 7 required in this message. 8

c. At least one instance of this element is required in this message. 9 Multiple instances of this element may be present in this message. 10

c. If the physical channel type is SCH, then the Extended Handoff 11 Direction Parameters Field Length shall be set to ‘0’ and the 12 following fields shall be ignored in the Cell Information Record: 13 QOF_Mask, PWR_Comb_Ind, Pilot_PN, and Code_Chan. 14

15

The following table shows the bitmap layout for the A3-Connect message modified to include Physical Channel Info IE. 16

7 6 5 4 3 2 1 0 Octet

⇒ Message Type II = [01H] 1




(LSB) 6 (MSB) 7


123


(LSB) 10



124





(LSB) 6


Length = [01H to 06H] 2 (MSB) SDU ID = <any value> 3

• • • • • • (LSB) n

⇒⇒⇒⇒ A3 Connect Information{1+: A3/A7 Element Identifier = [1BH] 1

Length = <variable> 2 Reserved = [000] Physical Channel Type

= [0H - IS-95 Fundamental Channel, 1H – Fundamental Channel (FCH), 2H – Supplemental Channel (SCH)

3H – Dedicated Control Channel (DCCH)],


(exist,new)

3


Cell Info Record {1+:

Cell Identification Discriminator = [02H] j (MSB) Cell = [001H-FFFH] j+1

(LSB) Sector = [0H-FH] (0H = Omni) j+2 Reserved = [000] QoF Mask =

[00, 01, 10, 11] New Cell

Indicator = [0,1]

(old, new)

PWR_Comb_Ind

= [0,1] (no,yes)

(MSB) K


} Cell Info Record



125


Length of Traffic Circuit ID = [05H] 1

Traffic Circuit ID {1:

Length of Traffic Circuit Identifier = [02H] 2 (MSB) Traffic Circuit Identifier = <any value> 3

(LSB) 4

Length of Traffic Connection Identifier = [01H] 5 Traffic Connection Identifier = [00H-FFH]

(AAL2 CID) 6

} Traffic Circuit ID Extended Handoff Direction Parameters Field Length = [09H] P

Extended Handoff Direction Parameters {1+:

Search Window A Size (Srch_Win_A) = [0H-FH]

Search Window N Size (Srch_Win_N) = [0H-FH]

p+1



p+2





p+4





} Extended Handoff Direction Parameters Length of Channel Element ID = <variable> Q


(LSB) …



126


Length of A3 Originating ID = [02H] R (MSB) A3 Originating ID = <any value> r+1

(LSB) r+2 Length of A7 Destination ID = [02H] s

(MSB) A7 Destination ID = <any value> s+1 (LSB) s+2

}A3 Connect Information

⇒⇒⇒⇒ Physical Channel Info: A3/A7 Element Identifier = [07H] 1

Length =[05H] 2 Frame Offset = [00H – FFH] 3

A3 Traffic Channel Protocol Stack = [001]

Pilot Gating Rate = [00, 01, 10]

ARFCN (high part) = [000-111]

4

ARFCN (low part) = [00H-FFH] 5 Count of Physical Channels = [01H-02H] 6

Reserved = [0000] OTD=[0,1]

Count of Physical Channels = [001 – 010]

6

Physical Channel 2 = 0H – N/A,

1H – FCH, 2H – SCH,

3H – DCCH

Physical Channel 1 = 0H – IS-95, 1H – FCH, 2H – SCH,

3H – DCCH

7

2

3 4


127


This message is used in the same format as the A3-Connect Ack message. 2

Refer to section 6.1.9.2, "A3-Connect Ack", TIA/EIA/IS-2001 3

In this case, message type “M” in A3 message will change to read “R”, and “C” to read 4 “O”. 5

6.2.14 Abis-Remove 6

This message is used in the same format as the A3-Remove message. 7

Refer to section 6.1.9.3, "A3-Remove", TIA/EIA/IS-2001 8


6.2.15 Abis-Remove Ack 11

This message is used in the same format as the A3-Remove Ack message. 12

Refer to section 6.1.9.4, "A3-Remove Ack", TIA/EIA/IS-2001 13


6.2.16 Abis-IS-2000 FCH Fwd 16

This message is used in the same format as the A3-IS-2000 FCH Forward message. 17

Refer to section 6.1.9.9, "Abis-IS-2000 FCH Forward", TIA/EIA/IS-2001 18


6.2.17 Abis-IS-2000 FCH Rvs 21

This message is used in the same format as the A3-IS-2000 FCH Reverse message. 22

Refer to section 6.1.9.10, "A3-IS-2000 FCH Reverse", TIA/EIA/IS-2001 23



This message is used in the same format as the A3-Traffic Channel Status message. 27

Refer to section 6.1.9.15, "A3-Traffic Channel Status", TIA/EIA/IS-2001 28


6.2.19 Abis-BTS Release Request 31

This message is sent from the BTS to the BSC to request de-allocation of resources. 32


128

1


Element Direction

Type

Message Type 7.2 BTS -> BSC R Call Connection Reference 7.10 BTS -> BSC R Cause 7.9 BTS -> BSC O Manufacturer’s Specific Records 7.7 BTS -> BSC O

2

The following table shows the bitmap layout for the Abis-BTS Release Request message: 3

7 6 5 4 3 2 1 0 Octet





(LSB) 6 (MSB) 7


(LSB) 10

⇒⇒⇒⇒ Cause: A1 Element Identifier = [04H] 1

Length = [01H] 2 ext = [0] Cause Value =

[07H (OAM&P intervention), 10H (Packet Data Going Dormant), 20H (equipment failure)]

3

⇒⇒⇒⇒ Manufacturer’s Specific Records: Abis Element Identifier = [70H] 1

Length = [variable] 2 Manufacturer ID = [00H – FFH] 3

Manufacturer’s specific information 4 • • • • • •

n 4


129

6.2.20 Abis-IS-2000 SCH Fwd 1

This message is used in the same format as the A3-IS-2000 SCH Forward message. 2

Refer to section 6.1.9.16, "A3-IS-2000 SCH Forward", TIA/EIA/IS-2001. 3


6.2.21 Abis-IS-2000 SCH Rvs 6

This message is used in the same format as the A3-IS-2000 SCH Reverse message. 7

Refer to section 6.1.9.17, "A3-IS-2000 SCH Forward", TIA/EIA/IS-2001. 8


6.2.22 Abis-IS-2000 DCCH Fwd 11

This message is used in the same format as the A3-IS-2000 DCCH Forward message. 12

Refer to section 6.1.9.13, "A3-IS-2000 DCCH Forward", TIA/EIA/IS-2001. 13


6.2.23 Abis-IS-2000 DCCH Rvs 16

This message is used in the same format as the A3-IS-2000 DCCH Reverse message. 17

Refer to section 6.1.9.14, "A3-IS-2000 DCCH Forward", TIA/EIA/IS-2001. 18


21

22

6.2.24 Abis-PACA Update 23

This Abis interface message is sent from the BSC to the BTS to update PACA related 24 information at the BTS. 25


Reference Element Direction

Type

Message Type 7.2 BSC -> BTS R Call Connection Reference 7.10 BSC -> BTS R Mobile Identity (IMSI) 7.4 BSC -> BTS O BTS PACA Order 7.32 BSC -> BTS Oa

a. This element identifies the PACA action to be taken. 27

The following table shows the bitmap layout for the Abis-PACA Update message: 28


130

1 7 6 5 4 3 2 1 0 Octet

⇒⇒⇒⇒ Message Type = [6EH] 1




(LSB) 6 (MSB) 7


(LSB) 10



Indicator = [1,0]


3


• • • • • •


⇒⇒⇒⇒ BTS PACA Order: A1 Element Identifier = [5FH] 1 Length = [02H] 2

Reserved PACA Action Required 2

3


131

7. Information Element Definitions 1

2

7.1 Information Element Identifiers 3

The following table contains lists of all elements that make up the messages defined in 4 Chapter 7. The table includes the Information Element Identifier (IEI) coding which 5 distinguished one element from another. 6

7

Table 7.1-1 Abis Information Element Identifiers Sorted by Identifier value 8

Element Name Identifier Interface(s) Reference

(unused value – available) 01H-02H Service Option 03H Abis, A1 7.17 Cause 04H Abis, A1 7.9 (unused value – available) 05H (unused value – available) 06H Quality of Service Parameters 07H Abis, A1 7.19 Abis Cell Info (Note: This Information Element is same with “A7 Cell Info” IE in TIA/EIA/IS-2001.)

08H Abis 7.16

(unused value – available) 09-0AH CDMA Target One Way Delay 0BH Abis 7.30 CDMA Serving One Way Delay 0CH Abis, A1, A7 7.24 Mobile Identity 0DH Abis, A1, A7 7.4 (unused value – available) 0E-10H Forward Burst Radio Info 11H Abis, A7 7.25 Reverse Burst Radio Info 12H Abis, A7 7.26 Correlation ID 13H Abis, A3, A7 7.3 IS-2000 Power Control Mode 14H Abis, A3 7.27 IS-2000 FPC Gain Ratio Info 15H Abis, A7 7.28 (unused value – available) 16-19H Cell Identifier List 1AH Abis, A1, A7 7.13 (unused value – available) 1B-1CH Privacy Info 1DH Abis, A7 7.12 (unused value – available) 1EH-20H Air Interface Message 21H Abis, A7 7.6


132

(unused value – available) 22H Layer 2 Ack Request/Results 23H Abis, A7 7.8 (unused value – available) 24H Downlink Radio Environment 29H Abis, A1, A7 7.23 (unused value – available) 2A-3EH Call Connection Reference 3FH Abis, A1, A3,

A7 7.10

(unused value – available) 40H Authentication Challenge Parameter 41H Abis, A1 7.33 (unused value – available) 42-4BH SDU ID 4CH Abis, A3, A7 7.14 (unused value – available) 4DH PACA Timestamp 4EH Abis, A1 7.18 (unused value – available) 4F-5CH Band Class 5DH Abis, A1, A7 7.11 (unused value – available) 5E PACA Order 5FH Abis, A1 7.32 (unused value – available) 60-70H Abis From ID 71H Abis 7.21 Abis To ID 72H Abis 7.22 BTS L2 Termination 73H Abis 7.29 Walsh Code Assignment Request 74H Abis 7.31 Abis Ack Notify 75H Abis 7.34

All other values are reserved. 1

2


133

7.2 Message Type 1

2

The Message Type element is used to indicate the type of a message on the Abis 3 interfaces. 4

Element Format: 5 7 6 5 4 3 2 1 0 Octet

Message Type 1 6

Table 7.2-1 Abis Message Type Values 7

Message Name

Message Type Value

Interface

Section

Reference

Abis-Connect 01H Abis Signaling Abis-Connect Ack 02H Abis Signaling Abis-Remove 03H Abis Signaling Abis-Remove Ack 04H Abis Signaling (unused value – available) 05H-0AH Abis-IS-2000 FCH Fwd 0BH Abis Traffic 6.2.16 Abis-IS-2000 FCH Rvs 0CH Abis Traffic 6.2.17 Abis-Traffic Channel Status 0DH Abis Traffic 6.2.18 Abis-IS-2000 DCCH Fwd 0EH Abis Traffic 6.2.22 Abis-IS-2000 DCCH Rvs 0FH Abis Traffic 6.2.23 Abis-IS-2000 SCH Fwd 10H Abis Traffic 6.2.20 Abis-IS-2000 SCH Rvs 11H Abis Traffic 6.2.21 (unused value – available) 12H-6DH Abis-PACA-Update 6EH Abis Signaling 6.32 (unused value – available) 6FH-7FH

8


134

(cont.) - Abis Message Type Values 1

Message Name

Message Type Value

Interface

Section

Reference

Abis-BTS Setup 80H Abis Signaling 6.2.5 Abis-BTS Setup Ack 81H Abis Signaling 6.2.6 Abis-BTS Release 82H Abis Signaling 6.2.7 Abis-BTS Release Ack 83H Abis Signaling 6.2.8 Abis-BTS Release Request 84H Abis Signaling 6.2.19 (unused value – available) 85H-8BH Abis-PCH Msg. Transfer 8CH Abis Signaling 6.2.3 Abis-PCH Msg. Transfer Ack 8DH Abis Signaling 6.2.4 Abis-ACH Msg. Transfer 8EH Abis Signaling 6.2.1 Abis-Burst Request 90H Abis Signaling 6.2.9 Abis-Burst Response 91H Abis Signaling 6.2.10 Abis-Burst Commit 92H Abis Signaling 6.2.11

All other values are reserved. 2

3

7.3 Correlation ID 4

Refer to section 6.2.2.108, “Correlation ID”, TIA/EIA/IS-2001. 5

6

7.4 Mobile Identity 7

Refer to section 6.2.2.16, “Mobile Identity”, TIA/EIA/IS-2001. 8

7.5 Cell Identifier 9

Refer to section 6.2.2.20, “Cell Identifier”, TIA/EIA/IS-2001. 10

7.6 Air Interface Message 11

Refer to section 6.2.2.152, “Air Interface Message”, TIA/EIA/IS-2001. ARQ fields 12 exchanged on an air-interface is not included in this information element. 13


135

7.7 UNUSED SECTION 1

2

7.8 Layer 2 Ack Request/Results 3

Refer to section 6.2.2.153, “Layer 2 Ack Request/Results”, TIA/EIA/IS-2001. 4 5

7.9 Cause 6

Refer to section 6.2.2.19, “Cause”, TIA/EIA/IS-2001. 7 8

7.10 Call Connection Reference 9

Refer to section 6.2.2.98, “Call Connection Reference”, TIA/EIA/IS-2001. 10 11

7.11 Band Class 12

Refer to section 6.2.2.106, “Band Class”, TIA/EIA/IS-2001. 13

7.12 Privacy Info 14

Refer to section 6.2.2.143, “Privacy Info”, TIA/EIA/IS-2001. 15 16

7.13 Cell Identifier List 17

Refer to section 6.2.2.21, “Cell Identifier List”, TIA/EIA/IS-2001. 18 19

7.14 SDU ID 20

Refer to section 6.2.2.91, “SDU ID”, TIA/EIA/IS-2001. 21

7.15 Physical Channel Info 22

Refer to section 6.2.2.14, “Physical Channel Info”, TIA/EIA/IS-2001. 23


136

7.16 Cell Information Record 1

Refer to section 6.2.2.89, “Cell Information Record”, TIA/EIA/IS-2001. 2 3

7.17 Service Option 4

Refer to section 6.2.2.66, “Service Option”, TIA/EIA/IS-2001. 5

7.18 PACA Timestamp 6

Refer to section 6.2.2.149, “PACA Timestamp”, TIA/EIA/IS-2001. 7

7.19 Quality of Service Parameters 8

Refer to section 6.2.2.54, “Quality of Service Parameters”, TIA/EIA/IS-2001. 9 10

7.20 Abis Connect Information 11

Refer to section 6.2.2.144, “A3 Connect Information”, TIA/EIA/IS-2001. 12

7.21 Abis Originating ID 13

This element contains an identifier chosen by the BSC (when the BSC sends an Abis 14 signaling message to the BTS) or BTS (when the BTS sends an Abis signaling message to 15 the BSC) for its own use in quickly processing Abis signaling messages received from the 16 BTS. For example, it may be used to identify the resources supporting the call 17 association that are internal to the BSC. If an Abis Originating ID is supplied by this BSC, 18 then the BTS includes this in the Abis Destination ID element in subsequent Abis 19 messages to this BSC. 20

21 7 6 5 4 3 2 1 0 Octet

Abis Element Identifier 1 Length 2

(MSB) Abis Originating ID 3 (LSB) • • •


137

Length: This field indicates the number of octets in this element 1 following the Length field. The maximum value in 2 this version of this specification is 8 octets. 3

Abis Originating ID: This field has variable length. The actual length is 4 indicated in the Length field and is dependent upon the 5 particular implementation. In this version of this 6 standard, this value shall be no more than 8 octets long. 7

7.22 Abis Destination ID 8

This element contains an identifier chosen by the BSC (when the BSC sends an Abis 9 signaling message to the BTS) or BTS (when the BTS sends an Abis signaling message to 10 the BSC) for its own use in quickly processing Abis signaling messages. 11

If an Abis Originating ID was supplied by the BSC, then the BTS includes this value in 12 the Abis Destination ID element in subsequent Abis messages to the BSC. 13

14 7 6 5 4 3 2 1 0 Octet


(MSB) Abis Destination ID 3 (LSB) • • •

Length: This field indicates the number of octets in this element 15 following the Length field. The maximum value in 16 this version of this specification is 8 octets. 17

Abis Destination ID: This field has variable length. The actual length is 18 indicated in the Length field and is dependent upon the 19 particular implementation. In this version of this 20 standard, this value shall be no more than 8 octets long. 21

7.23 Downlink Radio Environment 22

Refer to section 6.2.2.25, “Downlink Radio Environment”, TIA/EIA/IS-2001. 23 24

7.24 CDMA Serving One Way Delay 25

Refer to section 6.2.2.79, “CDMA Serving One Way Delay”, TIA/EIA/IS-2001. 26

27


138

7.25 Forward Burst Radio Info 1

Refer to section 6.2.2.56, “Forward Burst Radio Info”, TIA/EIA/IS-2001. 2 3

7.26 Reverse Burst Radio Info 4

Refer to section 6.2.2.57, “Reverse Burst Radio Info”, TIA/EIA/IS-2001. 5 6

7.27 IS-2000 Forward Power Control Mode 7

Refer to section 6.2.2.177, “IS-2000 Forward Power Control Mode”, TIA/EIA/IS-2001. 8 9

7.28 IS-2000 FPC Gain Ratio Info 10

Refer to section 6.2.2.178, “IS-2000 FPC Gain Ratio Info”, TIA/EIA/IS-2001. 11

12

7.29 BTS L2 Termination 13

This information element is used to indicate whether the BTS terminates Layer 2 or not. 14 In this release of the Abis specification L2 termination is mandatory to be supported by 15 the BTS and may be supported by the BSC. Therefore BTS L2 termination shall be set 16 “1” in this version. 17

7 6 5 4 3 2 1 0 Octet

Abis Element Identifier 1

Length 2 Reserved BTS L2

Termination

3

Length: The Length field is a binary value indicating the number of 18 octets following the Length field. 19

BTS L2 Termination: This bit shall be set to ‘0’ when the BTS dose not 20 terminate Layer 2, and be set to ‘1’ when the BTS 21 terminates Layer 2. 22

23


139

7.30 CDMA Target One Way Delay 1

The BSC uses this IE to send the CDMA Target One Way Delay to each target BTS 2 involved in soft handoff. 3

4 7 6 5 4 3 2 1 0 Octet


CDMA Target One Way Delay (high part) 3 CDMA Target One Way Delay (low part) 4

5 6

7.31 Walsh Code Assignment Reqest 7

This information element indicates the Walsh code in the message that this IE is sent is 8 invalid. 9

10 7 6 5 4 3 2 1 0 Octet


Length 2 11

Length: The Length field is set to ‘0’. 12

13

14

7.32 PACA Order 15

The purpose of this element is for the BSC to instruct the BTS to take appropriate action 16 upon receiving the Abis-PACA Update message. 17

18 7 6 5 4 3 2 1 0 Octet

A1 Element Identifier 1 Length 2

Reserved PACA Action Required 3

19


140

Length This field shall be set to the length of this element in octets following 1 the Length field. 2

The PACA Action Required field is coded as follows: 3

4

PACA Action Required

Value (binary)

Description

000 Reserved

001 Update Queue Position

010 Reserved

011 Remove MS from the queue

100 Reserved

101 Reserved

All other values reserved

5

Reserved This field shall be set to ‘00000’. 6

7

7.33 Authentication Challenge Parameter (RAND) 8

The Authentication Challenge Parameter information element provides a non-predictable 9 number which is used for authentication/SSD update. Bit 7 of octet 2 is the most 10 significant bit, while bit 0 of the highest numbered octet is the least significant bit. 11

7 6 5 4 3 2 1 0 Octet

A1 Element Identifier 1 Length 2

Reserved Random Number Type 3 (MSB) 4

RAND Value 5-m (LSB) m+1

Length: The Length field is a binary value indicating the number 12 of octets following the Length field. 13

Random Number Type: 14 Random Number Type

Value Random Number Type Random Number

Length

0001 RAND 32 bits


141

1 2

7.34 Abis Ack Notify 3

This information element is used to indicate whether the BSC wants to be informed that a 4 layer 2 ack was received from the MS. 5

6 7 6 5 4 3 2 1 0 Octet


Length 2

Length: The Length field is a binary value indicating the number of 7 octets following the Length field. 8

9

10


142

8. Timer Definitions 1

Table 8-1 describes the parameters values for each timer. Refer to section 6.3 “Timer 2 Definitions”, TIA/EIA/IS-2001, for the MSC timers (T10, T301, T315, T3113). 3

Table 8-1 Timer Values and Range 4

Timer Name Default Value (seconds)

Range of Values

(seconds)

Granularity (seconds)

Section Reference

Timer Location

Tconnb 0.1 0 – 1.0 0.1 8.1 BTS

Tsetupb 0.1 0 – 0.5 0.1 8.2 BSC

Tchanstatb 0.5 0 – 1.0 0.1 8.3 BSC

Tdisconb 0.1 0 – 1.0 0.1 8.4 BTS

Tdrptgtb 0.5 0 – 1.0 0.1 8.5 BSC

Tbstreqb 0.5 0 – 1.0 0.1 8.6 BSC

Tbstcomb 0.5 0 – 1.0 0.1 8.7 BTS

Trelreqb 0.1 0 – 1.0 0.1 8.8 BTS

5

6

8.1 Tconnb :Timer for Abis-Connect message 7

This BTS timer is started when the Abis-Connect message is sent, and stopped when the 8 Abis-Connect Ack message is received. 9

10

8.2 Tsetupb : Timer for Abis-BTS Setup message 11

This BSC timer is started when the Abis-BTS Setup message is sent, and stopped when 12 the Abis-Connect message is received. 13

14

8.3 Tchanstatb : Timer for Abis-Traffic Channel Status message 15

The Tchanstatb timer is used by the BSC to wait for the Abis-Traffic Channel Status 16 message for all new cells on an Abis connection. This timer is started when the 17 Abis-Connect Ack message indicating that Abis-Traffic Channel Status messages are 18 requested is sent and stopped when Abis-Traffic Channel Status message(s) have been 19 received for all new cells on the Abis connection. 20

21


143

8.4 Tdisconb : Timer for Abis-Remove Ack message 1

The Tdisconb timer is used by the BTS to wait for the Abis-Remove Ack message. This 2 timer starts when the BTS sends Abis-Remove message, and stops when the BTS 3 receives the Abis-Remove Ack message. 4

5

8.5 Tdrptgtb : Timer for Abis-BTS Release Ack message 6

The Tdrptgtb timer is used by the BSC to wait for Abis-BTS Release Ack message. This 7 timer starts when the BSC sends the Abis-BTS Release message and stops when the BSC 8 receives the Abis-BTS Release Ack message. 9

10

8.6 Tbstreqb : Timer for Abis-Burst Response message 11

The Tbstreqb timer is used by the BSC to wait for Abis-Burst Response message. This 12 timer starts when the BSC sends the Abis-Burst request message and stops when the BSC 13 receives the Abis-BTS Release Ack message. 14

15

8.7 Tbstcomb : Timer for Abis-BTS Release Ack message 16

The Tbstcomb timer is used by the BTS to wait for Abis-Burst Commit message. This 17 timer starts when the BTS sends the Abis-BTS Release message and stops when the BTS 18 receives the Abis-Burst Commit message. 19

20

21

8.8 Trelreqb : Timer for Abis-BTS Release message 22

The Trelreqb timer is used by the BTS to wait for Abis-BTS Release message. This timer 23 starts when the BTS sends the Abis-BTS Release Request message and stops when the 24 BTS receives the Abis-BTS Release message. 25

26

abis interface

Documents

abisbts setup

use of atm layer

atm adaptation layer

3gpp2 requests

issue documents

standards publications

standards committee

network reference model