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ALCATEL-LUCENT WIMAX SOLUTION

ALCATEL-LUCENT 9160 WIMAX ACCESS CONTROL

Alcatel-Lucent WiMAX Access Control



TABLE OF CONTENT

1 ALCATEL-LUCENT WIMAX RADIO ACCESS SOLUTION .............................4 2 WAC MAIN FUNCTIONS IN WIMAX SYSTEM ............................................6

2.1 ROLE OF WAC ..................................................................................................... 6 2.2 WIMAX NETWORK ARCHITECTURE WITH INTERCONNECTION TO A SINGLE CSN ................. 7 2.3 WIMAX NETWORK ARCHITECTURE WITH RAN SHARING ................................................. 8

3 ACCESS CONTROL CONFIGURATIONS IN RELEASE W2 ...........................9 3.1 WAC CONFIGURATIONS IN RELEASE W2................................................................... 9 3.2 WAC DATA IN RELEASE W2 CONFIGURATIONS ....................................................... 11

3.2.1 DIMENSIONS, CONSUMPTION AND WEIGHT OF WAC................................................................11 3.2.2 ENVIRONMENTAL DATA .........................................................................................................12 3.2.3 CAPACITY OF ACCESS CONTROLLER .........................................................................................12 3.2.4 NUMBER OF IP ADDRESSES OF WAC IN RELEASE W2...................................................................12 3.2.5 RELIABILITY OF ACCESS CONTROLLER........................................................................................13

3.3 FIELD TRIAL WAC CONFIGURATIONS IN RELEASE W2 ................................................. 14 3.3.1 DESCRIPTION OF FIELD TRIAL CONFIGURATIONS.........................................................................14 3.3.2 DIMENSIONS, CONSUMPTION AND WEIGHT OF FIELD TRIAL WAC .................................................17

4 ACCESS CONTROL CONFIGURATIONS IN RELEASE W3 .........................18 4.1 WAC CONFIGURATIONS IN RELEASE W3................................................................. 18 4.2 WAC REDUNDANCY............................................................................................ 21 4.3 WAC DATA IN RELEASE W3 CONFIGURATIONS ....................................................... 23

4.3.1 DIMENSIONS, CONSUMPTION AND WEIGHT OF WAC................................................................23 4.3.2 ENVIRONMENTAL DATA .........................................................................................................23 4.3.3 CAPACITY OF ACCESS CONTROLLER .........................................................................................24 4.3.4 NUMBER OF IP ADDRESSES OF WAC IN RELEASE W3..................................................................24 4.3.5 RELIABILITY OF ACCESS CONTROLLER........................................................................................25

4.4 FIELD TRIAL WAC CONFIGURATIONS IN RELEASE W3 ................................................. 26 5 WAC SERVER FUNCTIONAL ARCHITECTURE ...........................................31

5.1 SESSION CONTROL FUNCTION .............................................................................. 31 5.2 OPERATION AND MAINTENANCE FUNCTION ............................................................. 32 5.3 DATA TRANSPORT FUNCTION................................................................................. 33


Ref.: File Date Edition 0/01/2007 1p7 3/36


6 INTERCONNECTION OF ACCESS CONTROLLER WITH OTHER NETWORK ELEMENTS.....................................................................................34

6.1 INTERCONNECTION OF ACCESS CONTROLLER WITH BASE STATIONS .............................. 34 6.2 INTERCONNECTION OF WAC SERVER WITH OTHER WAC SERVERS................................. 35 6.3 INTERCONNECTION OF ACCESS CONTROLLER WITH HOME AGENT ............................... 36 6.4 INTERCONNECTION OF ACCESS CONTROLLER WITH SBC ............................................ 36




1 ALCATEL-LUCENT WIMAX RADIO ACCESS SOLUTION Typically, a WiMAX Access system comprises four basic elements: the User Equipment, the Base Station (BS), the Access Control and an Operation & Maintenance Center as pictured in Figure 1.

Operation &

Maintenance Base

Station Nomadic Terminals

Access Control

Operation &

Maintenance Base

Station

W-DSL Terminals

Nomadic Terminals

Access Control

Figure 1: WiMAX Access System

User Equipment / Subscriber Station Several 802.16e User Equipments are available on the market depending on the service to be offered:

• Customer Premises Equipment – CPE Self install and plug & play indoor modem to offer Wireless DSL services, at home or at office, including several options, such as Voice Over IP or WiFi access point. Outdoor CPE for large cell coverage.

• Nomadic User Equipments Laptops or PDAs can be equipped with WiMAX PCMCIA cards based on 802.16e .

Base Station (BS) Base Station connects Subscriber Station to a wired network and serves as the wireless equivalent of a LAN hub. A WiMAX access network with connectivity to the wired network comprises several BS that have some area of overlap so that mobile devices can roam from one BS to the next seamlessly. WiMAX Access Control The WiMAX Access Control (WAC) provides the connectivity for the SS/MSS with the rest of the network (corporate network, internet, Core Network, etc). It plays a vital role during the authentication and authorization of the user. Based upon the results of authentication, it may allow the user to access the network, access some limited local services or deny the access.




The WiMAX Access Control consists of a cabinet housing: • The Access Controller Cluster comprising WAC Switch(es) and WAC Server(s). • Optional Core Network central functions participating in Access Control:

o Home Agent/Router. o AAA Server. o DHCP Server. o Session Border Controller.

Operation & Maintenance Center The Alcatel-Lucent WiMAX OMC-R will help you in your network deployment while ensuring optimal Quality of Service (QoS). With the integration of a full set of management features geared to network's special needs and ready to slide right into operator’s information system. The Alcatel-Lucent 1353 WiMAX OMC-R performs network surveillance, quality of service monitoring and radio network planning/optimization for the WiMAX Access Network. This low-cost, future-proof solution, based on GSM and UMTS Alcatel-Lucent OMC-R, can be integrated seamlessly into existing IT systems, and comes with a complete set of advanced management features:

• Easy interface with Radio Network Planning (RNP) application for trouble-free implementation of your network during deployment and densification.

• Network plug & play functions. • Provisioning and template-based radio configuration. • Highly intuitive man-machine interface. • Full set of QoS indicators and predefined or customized QoS reports give full network performance

visibility. • RNO (Radio Network Optimizer) embedded in OMC-R. • Scalable capacity, up to 2000 cells.




2 WAC MAIN FUNCTIONS IN WIMAX SYSTEM 2.1 Role of WAC Inside the WiMAX Radio Access Network (RAN), the Wireless Access Control (WAC) is responsible for subscribers’ Access Control, IP Connectivity, Traffic Routing inside the RAN and with external networks. Additionally, WAC provides Mobility and Security Support within the RAN, and QoS Support within the RAN in coordination with Core Network. Access control consists mainly in:

• Authenticating users against RAN and target network access. • Controlling subscribers access to resources (authorization according to users’ profile). • Providing accounting information on radio resource usage to network operator.

IP Connectivity services consists mainly in providing an IP address to the user’s equipment. The WAC will act as a DHCP relay entity. According to the various configurations, the local address provided to the subscriber can be a public or private address. WAC’s Mobility Support consists mainly in:

• Proxy Mobile IP (PMIP) function: WAC sets up MIP registrations with the Home Agent (HA) on behalf of the client.

• Foreign Agent (FA) function: the WAC tunnels user’s packets to the Home Agent. • Relaying of user’s context during handoff between source and target BS. • Paging Controller function. WAC stores information related to Mobile Stations that are in Idle Mode.

Traffic Routing consists mainly in: • Routing subscribers’ traffic between the Base Stations and the Network Services Provider networks. • Establishment of inter-WAC tunnels in case of inter-WACs handoffs.

Security Support consists mainly in: • 802.16e AK keys calculation and transmission to BS.

QoS Support consists mainly in: • CAC admission control at WAC level. • Relaying QoS control plane commands coming from Core Network and performing CAC in

coordination with the BS (PDF function), and creating appropriate Service Flows over the air (PEF function).




2.2 WiMAX network architecture with interconnection to a single CSN This architecture is available from Release W2.

BS

BS

BS

Transport&

Aggregationnetwork

WAC

OMC-R

HA Routeror

RouterFW

INTERNET

BS

BS

BS

Transport&

Aggregationnetwork

AAA

PSTN

SessionBorder

Controller

SIPController Voice

Gateway

RAN entity

SS

WAC

DHCP

DNS

CSN entity ASP entity

StreamingServer

VideoController

StreamingEncoder

MediaContent

CSN

ASP

RANDHCP/DNS for BS & WAC

Figure 2: architecture of WiMAX RAN with interconnection to a single CSN

Figure 2 shows the Radio Access Network (RAN) and its interconnection with a single Core Services Network (CSN) and an Application Services Provider network (ASP). Base Stations and WACs obtain their IP addresses via DHCP and DNS servers of the Transport and Aggregation Network or from those embedded in the OMC-R. Core Services Network Networks Elements include:

o Router with or without Home Agent function � Home Agent function is mandatory when Mobility Service is to be offered. � For Fixed Wireless Service Home Agent function is not necessary.

o DHCP server(s) used for IP address allocation to Subscriber Stations o DNS server(s) used to map URIs of machines to their IP addresses. o Firewall(s) to protect RAN NEs and RAN users from attacks.




2.3 WiMAX network architecture with RAN sharing This architecture is supported from Release W3.

SS BS

WAC

BSSS

BGRouter

CSN 1

CSN 2

CSN 3

ASPs

+

Internet

RAN CSNsSSs

Figure 3: WiMAX RAN architecture with interconnection to several CSNs

Figure 3 shows the RAN and its interconnection with severql Core Services Networks (CSNs) and Application Services Provider network (ASPs). This architecture is supported for the Fixed and Nomadic Access only as there are no Home Agents in this architecture. In this architecture RAN resources are shared between different Network Services Providers. Specific QoS mechanisms are used in the WAC (CAC, flow policing) and RAN Transport Network (VLAN or DSCPbased QoS enforcement) to share resources according to the different SLAs.




3 ACCESS CONTROL CONFIGURATIONS IN RELEASE W2 In Release W2, WAC is available in two configurations WAC and Field Trial WAC. These configurations are N+0 configurations, with N=1 to 4, for a total capacity from 500 Mbps to 2 Gbps. 3.1 WAC Configurations in Release W2 WAC is available with one to 4 servers configurations as shown in Figure 4.

Power Distribution Unit

CONSOLE

OmniSwitch 6800-24

23

2 4 6 108 12

OK PRI

PWR RPS

FAN T EMP

SFP 1 XFP 2

24

21

22

LINK

ACT

LINK

ACT14 16 18 2220 24

1 3 5 97 11 13 15 17 2119 23

Server

Server

Server 1 to 4 servers

Electrical/Optical portsto RAN & CN

LAN Switch

Figure 4: WAC configurations in Release W2

Base components: • 24 U cabinet with pre-equipment to accept optional elements (Power Distribution units, slides, …) • one WAC WAC Switch Alcatel-Lucent 6800-24 or 6850-24X • one WAC Server Dell PowerEdge 1850 or PowerEdge 1950

Optional components: • 1 to 4 SX or LX 1 Gbps optical interface(s) for WAC Switch/Router • 1 to 3 additional WAC Servers




Interconnections inside the WAC Cluster between WAC Server and WAC Switch are shown in Figure 5.

WACEthernet Switch

2/2WAC

Ethernet Switch1/2

WAC Server1

User plane processingControl plane processing

Operation and Maintenance

1 GE 1 GE1 GE

1 GE

to BS to CN

WAC ServerN



1 GE 1 GE

1 GE

1 GE

Electricalor Optical

Electricalor Optical

2 halves of single switch Figure 5: Interconnections of WAC Servers and WAC Switch

In Release W2: Each BS is connected to a unique WAC Server. Each WAC Server is seen as an independent unit by the OMC-R. The WAC Switch aggregates traffic of the WAC Servers and is the interconnection device to other RAN and CN nodes. Up to 4 1GE Electrical or Optical connections are available on the WAC Switch.




3.2 WAC DATA in Release W2 Configurations 3.2.1 Dimensions, Consumption and Weight of WAC Table 1 and Table 2 give the Physical Data of WAC in Release W2 Configurations. Theses tables include data with the two hardware generations.

Configurations 500 Mbps 1000 Mbps 1500 Mbps 2000 Mbps Dimensions H * W * D (mm) 1200 * 607 *1001

Weight (kg) 154 172 190 207 Consumption (kW) 0.61 1.11 1.61 2.11

Number of WAC Servers PowerEdge 1850

1 2 3 4

Number of WAC Switches Omniswitch 6800-24

1 1 1 1

External Connections 4 ports 10/100/1000 Mbps Ethernet electrical or 4 ports 1GE optical SR or LR

Table 1: Physical Data for WAC in Release W2 Configurations (1st gen. Hardware) Configurations 500 Mbps 1000 Mbps 1500 Mbps 2000 Mbps

Dimensions H * W * D (mm) 1200 * 607 *1001 Weight (kg) 152 168 185 201

Consumption (kW) 0.494 1.11 1.61 2.11 Number of WAC Servers

PowerEdge 1950 1 2 3 4

Number of WAC Switches OmniSwitch 6850-24X

1 1 1 1

External Connections 4 ports 10/100/1000 Mbps Ethernet electrical or 4 ports 1GE optical SX or LX

Table 2: Physical Data for WAC in Release W2 Configurations (2nd gen. Hardware)




3.2.2 Environmental Data Operating Climatic Range: 10-35°C Operating Humidity Range: 8-85%

3.2.3 Capacity of Access Controller Capacity of WAC grows linearly with the number of WAC units offering a scalable capacity from 500 Mpbs to 2000 Mbps in 500 Mbps steps. The capacity of the various WAC configurations in shown in Table 3.

Number of active WAC Servers in WAC Cluster

Maximum number of supported BS carriers

Maximum number of supported users (active or idle)

Maximum throughput (Mbps)

1 200 60 000 500 2 400 120 000 1000 3 600 180 000 1500 4 800 240 000 2000

Table 3: WAC capacity vs. configurations in Release W2

3.2.4 Number of IP addresses of WAC in Release W2 Lists the number of IP addresses in release W2.

WAC Cluster Unit RAN side CN side Per Server One IP address for:

o Control Plane (to BSs) o Management Plane (to OMC-R) o User Plane

One IP address for: o Control Plane o User Plane

Switch One IP address for Management Plane Table 4: Number of WAC IP addresses in Release W2




3.2.5 Reliability of Access Controller At Server level: Each WAC server unit is equipped with redundant hot-swappable Power Supplies and Hard Disks. Faulty PS or HD can be replaced without opening the server. Fans are multi-redundant in each WAC server. At Cluster level: Reliability figures are given in Table 5.

Configuration 500 Mbps

1000 Mbps 1st generation hardware

500 Mbps 1000 Mbps

2nd generation hardware

Number of WAC Servers 1 to 4 1 to 4 Number of WAC Switches 1 1

Availability (%) MTTR = 4 h

99.991 99.992

MTBF (h) of WAC Server 65 567 72 400 MTBF (h) of WAC Switch 131 489 178 670

Table 5: Reliability figures in Release W2 configurations




3.3 Field Trial WAC Configurations in Release W2 3.3.1 Description of Field Trial Configurations Field Trial WAC Configurations are shown in Figure 6.

CONSOLE

OmniSwitch 6800-24

23

2 4 6 108 12

OK PRI

PWR RPS

FAN TEMP

SFP1 XFP2

24

21

22

LINK

ACT

LINK

ACT14 16 18 2220 24

1 3 5 97 11 13 15 17 2119 23

Power Distribution Unit

CONSOLE

OmniSwitch 6800-24

23

2 4 6 108 12

OK PRI

PWR RPS

FAN TEMP

SFP1 XFP2

24

21

22

LINK

ACT

LINK

ACT14 16 18 2220 24

1 3 5 97 11 13 15 17 2119 23

HA/Router

Server

AAA server

DHCP

Server

Access Controller

24 Ucabinet

aggregation switchor

aggregation switch/router

IP addressing

EAP AuthenticationAuthorizationAccounting

HA/Router: anchor point for mobility

WAC LAN Switch

WAC Server

LAN Switch

LAN Switch

Figure 6: Field Trial WAC configurations in Release W2




In order to address the case of Field Trial and small deployments, the WiMAX Access Control Cabinet includes the following network elements: Base components:

• 24 U cabinet with pre-equipment to accept optional elements (Power Distribution units, slides, …) • one WAC Switch/Router Alcatel-Lucent 6800-24 or 6850-24X • one WAC Server Dell PowerEdge 1850 or Dell PowerEdge 1950

Optional components: • 1 to 3 additional WAC Servers • one aggregation LAN Switch/Router Alcatel-Lucent 6800-24 or 6850-24X • one Home Agent/Router Cisco 3845 • one AAA server (1U IT sever). Supports EAP-TTLS/CHAP. • one DHCP server (1U IT server)

The above Cabinet Configuration has the following characteristics:

• The DHCP server handles the IP addressing needs of the Subscriber Stations. • The AAA server handles Authentication, Authorization and Accounting of users. Users’ credentials can

be stored in a local database. The aggregation switch interconnects the optional Central Function Network Elements. In the architecture for Fixed Wireless usage, it is also used as an Access Router.




The interconnection diagrams corresponding to the two architectures (with or without Home Agent) are shown in Figure 7 and Figure 8:

WAC Controller

DHCP server

WAC SwitchHA

Router

to BS

WAC Server

WAC Server AAA server

InternetWeb servers

AuxiliaryLANSwitch

ManagementHA/AAA server/DHCP

WAC cabinetincluding central functions

OMC-R

Figure 7: FT WAC interconnections (case with HA)

WAC Controller

DHCP server

WAC Switch

to BS

WAC Server

WAC Server AAA server

InternetWeb servers

AuxiliaryLANSwitch



OMC-R

Router

Figure 8: FT WAC interconnections (case without HA)




3.3.2 Dimensions, Consumption and Weight of Field Trial WAC Table 6 gives the Physical Data of WAC in Release W2 Configurations.

Configuration 500 Mbps Mobile Service

500 Mbps Fixed Service

Dimensions : H * W * D (mm) 1200 * 607 *1001 Weight (kg) 227 206

Consumption (kW) 1.85 1.61 WAC Server: PowerEdge 1850 1 1

WAC Switch: OmniSwitch 6800-24 2 1 WAC Switch/Router: OmniSwitch 6800-24 1

HA Router: Cisco 3845 1 DHCP Server: PowerEdge 1850 1 1

AAA Server: PowerEdge 850 1 1 Table 6: Physical Data of FT WAC in Release W2 configurations (1st gen. Hardware)

Configuration 500 Mbps

Mobile Service

500 Mbps Fixed Service

Dimensions: H * W * D (mm) 1200 * 607 *1001 Weight (kg) 227 206

Consumption (kW) 1.85 1.61 WAC Server: PowerEdge 1950 1 1

WAC Switch: OmniSwitch 6850-24X 2 1 WAC Switch/Router: OmniSwitch 6850-24X 1

HA Router: Cisco 3845 1 DHCP Server: PowerEdge 1950 1 1 AAA Server: PowerEdge 1950

PowerEdge 1950 1 1

Table 7: Physical Data of FT WAC in Release W2 configurations (2nd gen. Hardware)




4 ACCESS CONTROL CONFIGURATIONS IN RELEASE W3 In Release W3, several significant enhancements are introduced:

o Modular High capacity configurations up 10 Gbps. o High Availability through Redundant Configurations of WAC Server and WAC Switch. o External Links redundancy. o 1 Gbps throughput per Server. o 10 GE optical connectivity for High Capacity Configurations , 4 to 10 Gbps.

4.1 WAC Configurations in Release W3 WAC Configurations in W3 are shown in Figure 9 and in Figure 10:

o 1 Gbps with no redundancy (500 Mbps in case of Legacy PowerEdge 1850 Server) o 2, 4, 6, and 10 Gbps with High Availability

The 2, 4, 6 and 10 Gbps configurations consist of: o 2N active WAC Servers + 1 or 2 Standby WAC Servers. o 2 or 3 active WAC switches (according to capacity).

WAC Server 3

WAC Server 2

WAC Server 1

LAN Switch 2

LAN Switch 1

Configuration 2 GbpsHigh Availability

WAC Server 1

LAN Switch 1

Configuration 1 Gbps

Figure 9: 1 Gbps (Non-Redundant) & 2 Gbps High Availability Configurations




WAC Server 12

WAC Server 11

WAC Server 10

WAC Server 9

WAC Server 8

WAC Server 7

WAC Server 6

WAC Server 5

WAC Server 4

WAC Server 3

WAC Server 2

WAC Server 1

LAN Switch 3

LAN Switch 2

LAN Switch 1


WAC Server 7

WAC Server 6

WAC Server 5

WAC Server 4

WAC Server 3

WAC Server 2

WAC Server 1

LAN Switch 3

LAN Switch 2

LAN Switch 1


WAC Server 5

WAC Server 4

WAC Server 3

WAC Server 2

WAC Server 1

LAN Switch 2

LAN Switch 1


Figure 10: 4, 6 & 10 Gbps High Availability Configurations

Interconnections inside the WAC Cluster between WAC Server and WAC Switch are shown in Figure 5.




WAC UNIT1



1 GE

1 GE

to BS

WAC UNIT2



1 GE 1 GE

WAC UNIT2N+1 or 2



1 GE 1 GE

10 GE

10 GE

1 GE 1 GE

1 GE

1 GE 1 GE

1 GE1 GE

1 GE

to CN

1 GE

1 GE

10 GE

10 GE

1 GE

1 GE

Stacking cables

to BS

to CN

WACSwitch

1

WACSwitch

2

1 GE

Figure 11: Interconnections of WAC Servers and WAC Switches

In Release W3: Each BS is connected to a unique WAC Server. OMC-R communicates with each WAC unit, whether active and standby, and associates them in a Cluster view. The WAC Switches aggregates traffic of the WAC Servers and are the interconnection device to other RAN and CN nodes. Up to 8 1GE Electrical or Optical and 4 10GE Optical connections are available on the WAC Switches.




4.2 WAC Redundancy At Server level: Each WAC server unit is equipped with redundant hot-swappable Power Supplies and Hard Disks. Faulty PS or HD can be replaced without opening the server. Fans are multi-redundant in each WAC server. At Cluster level: WAC Servers are organized in 2N active plus one or two standby WAC Servers, according to capacity. The active WAC Servers are organized in mated pairs, each server mirroring each other’s data in real-time. If one server becomes faulty, Standby WAC Server takes over, taking the role of active server, retrieving the data of the faulty server via its mated running WAC Server. WAC Servers Failover mechanism is based on a Layer 3 Alcatel-Lucent proprietary protocol. When the faulty uni is replaced, it is elected as Standby unit. There WAC Switches are all active, with a 1 + 1 or 2+1 active redundancy, depending on the Cluster capacity, with redundant stacking cables interconnecting them. WAC Switches failover mechanism is based on an Alcatel-Lucent proprietary. Internal links, between WAC Servers and Switches are protected at Layer 2 (bonding). External links , towards RAN and CN are 1+1 protected with 2 possible failover mechanisms:

o Link aggregation. o Spanning Tree.

Table 8 lists the different configurations.

Configuration 2 Gbps High

Availability

4 Gbps High

Availability

6 Gbps High

Availability

10 Gbps High

Availability Number of WAC

Servers Active + Standby

2 + 1 4 + 1 6 + 1 10 + 2

Number of Switches 1 + 1 1 + 1 2 + 1 2 + 1 Table 8: WAC Cluster Redundancy configurations




The Redundant Architecture of the 2 Gbps configuration is detailed in Figure 12.

WACServerUNIT

BSLink1

CNLink1

CN_1

BSLink2

CNLink2

BS

BS

RANtransportnetwork

Core Network

link aggregation

link aggregation

CN_2

BS_1

BS_2

WACServerUNIT

CN_1

CN_2

BS_1

BS_2

WACServerUNIT

CN_1

CN_2

BS_1

BS_2

Redundant unit

WAC Switch

WAC Switch

Figure 12: 2 Gbps High Availability architecture

There are two active WAC Switches (1 + 1 active redundancy), with 2 stacking cables joining them. WAC Switches failover mechanism is Alcatel-Lucent proprietary. There are two active WAC Servers and one Standby WAC Server. WAC Servers failover mechanism is proprietary. The two active WAC Servers mirror each other’s data in real-time. If one becomes faulty, Standby WAC Server takes over, retrieving data of the faulty server, via its mated WAC Server. When Standby Server takes over, its retrieves the IP addresses of the faulty unit, making the switchover transparent to other NEs. Internal links, between WAC Servers and Switches are protected at Layer 2 (bonding). External links , towards RAN and CN are 1+1 protected with 2 possible failover mechanisms:

o Link aggregation. o Spanning Tree.




4.3 WAC DATA in Release W3 Configurations 4.3.1 Dimensions, Consumption and Weight of WAC Table 9 gives the Physical Data of WAC in Release W3 Configurations. This table includes data with the new hardware generations PowerEdge 1950 & Omniswitch 6850-24X. For 1st generation hardware, applicable only to non-redundant configuration with a single server, please refer to W2 data. Optical SX and SR options correspond to 300 m range. Optical LX and LR options correspond to 10 km range.


2 Gbps High

Availability

4 Gbps High

Availability

6 Gbps High

Availability

10 Gbps High

Availability Number of WAC

Servers Active + Standby

1 + 0 2 + 1 4 + 1 6 + 1 10 + 2

Number of Switches 1 1 + 1 1 + 1 2 + 1 2 + 1 External Connections 8 ports 11/100/1000 Mbps

Ethernet electrical or

8 ports 1GE optical SX or LX or

4 ports 10GE optical SR or LR

4 ports 10GE optical SR or LR

Dimensions H * W * D (cm)

1200 * 607 *1001

Weight (kg) 152 190 223 261 342 Consumption (kW) 0,50 1,25 2,11 3,03 5,01

Table 9: Physical Data of FT WAC in Release W2 configurations (2nd gen. Hardware)

4.3.2 Environmental Data Operating Climatic Range: 10-35°C Operating Humidity Range: 20-80%




4.3.3 Capacity of Access Controller Capacity of WAC grows linearly with the number of WAC units offering a scalable capacity. The capacity of the various WAC configurations in shown in Table 10.

Configuration Maximum number of supported BS carriers

Maximum number of supported users (active or idle)

Maximum throughput (Gbps)

500 Mbps (PowerEdge 1850)

500 60 000 0.5

1 Gbps 500 60 000 1 2 Gbps 1000 120 000 2 4 Gbps 2000 240 000 4 6 Gbps 2000 360 000 6

10 Gbps 2000 600 000 10 Table 10: WAC capacity vs. configurations in Release W3

Remarks: o WBS represents a BS carrier. o OMC-R can supervise 2000 BS carriers max.

4.3.4 Number of IP addresses of WAC in Release W3 Lists the number of IP addresses in release W3.

WAC Cluster Unit RAN side CN side Per Server One IP address for Management Plane

One IP address for Control Plane whatever the number of CSNs One IP address for User Plane per CSN for WAC-BS communication One IP address for User Plane per CSN for WAC-WAC communication

One IP address for Control Plane per CSN. One IP address for User Plane per CSN.

Per Switch One IP address for Management Plane Table 11: Number of WAC IP addresses in Release W3




4.3.5 Reliability of Access Controller At Server level: At each WAC server level redundant hot-swappable Power Supply and Hard Disk are provided. Faulty PS or HD can be replaced without opening the server. Fans are multi-redundant in each WAC server. At Cluster level: Reliability figures are given in Table 12.


2 Gbps High

Availability

4 Gbps High

Availability

6 Gbps High

Availability

10 Gbps High

Availability Availability (%) MTTR1 = 48h

MTTR2 = MTT3 = 24h

99.907

99.999 9

99.999 6

99. 999 1

99.999 97

MTBF (h) of WAC Server

72 400

MTBF (h) of WAC Switch

178 670

Number of WAC Servers

Active + Standby

1 + 0

2 + 1

4 + 1

6 + 1

10 + 2

Number of Switches 1 1 + 1 1 + 1 2 + 1 2 + 1 Table 12. Reliability figures in Release W3 configurations




4.4 Field Trial WAC Configurations in Release W3 Field Trial WAC Configurations are shown in Figure 13 and in Figure 14.

WAC Server 1

LAN Switch 1

Auxiliary LAN Switch/Router

Session Border Controller

DHCP Server

AAA Server

FT Configuration 1 GbpsMobile Service

FT Configuration 1 GbpsFixed Service

WAC Server 1

LAN Switch 1

Auxiliary LAN Switch


DHCP Server

AAA Server

HA Router

Figure 13: Field Trial WAC configurations in Release W3 (case of one server)




Case of single WAC Server configurations: In order to address the case of Field Trial and small deployments, the WiMAX Access Control Cabinet includes the following network elements: Base components:

• 24 U cabinet with pre-equipment to accept optional elements (Power Distribution units, slides, …) • one WAC Switch/Router Alcatel-Lucent 6800-24 or 6850-24X • one WAC Server Dell PowerEdge 1850 or Dell PowerEdge 1950

Optional components: • one aggregation Switch/Router Alcatel-Lucent 6800-24 or 6850-24X • one Home Agent/Router Cisco 3845. • one AAA server (1U IT sever). Supports EAP-TTLS/CHAP. • one DHCP server (1U IT server). • one Session Border Controller (1U IT server).

Remark: This configuration supports two WAC hardware generations: o PowerEdge 1850 and OmniSwitch 6800-24 o PowerEdge 1950 and OmniSwitch 6850-24X




WAC Server 3

WAC Server 2

WAC Server 1

LAN Switch

LAN Switch

Auxiliary LAN Switch/Router


DHCP Server

AAA Server

FT Configuration 2 GbpsHigh AvailabilityMobile Service

FT Configuration 2 GbpsHigh Availability

Fixed Service

WAC Server 3

WAC Server 2

WAC Server 1

LAN Switch

LAN Switch

Auxialiary LAN Switch


DHCP Server

AAA Server

HA Router

Figure 14: Field Trial WAC configurations in Release W3 (case 2 servers with

redundancy)




Case of dual active WAC Servers configuration with redundancy: In order to address the case of Field Trial and small deployments, the WiMAX Access Control Cabinet includes the following network elements: Base components:

• 24 U cabinet with pre-equipment to accept optional elements (Power Distribution units, slides, …) • two WAC Switch/Router Alcatel-Lucent 6850-24X • three WAC Servers Dell PowerEdge 1950

Optional components: • one aggregation LAN Switch/Router Alcatel-Lucent 6850-24X • one Home Agent/Router Cisco 3845. • one AAA server (1U IT sever). Supports EAP-TTLS/CHAP. • one DHCP server (1U IT server). • one Session Border Controller (1U IT server).

Remark: This configuration supports only new WAC hardware generation: o PowerEdge 1950 and OmniSwitch 6850-24X


Ref.: File Date Edition /01/2007 1p7 30/36


Figure 7 and Figure 8 show the two typical interconnection diagrams:

WAC Controller

DHCP server

WAC Switch HARouter

to BS

Session BorderController

WAC ServerWAC Server

AAA server

InternetWeb servers

Voice and VideoServices

AuxiliaryLANSwitch



OMC-R

WAC Server

WAC Switch

Figure 15: FT WAC interconnections (case with HA)

WAC Controller

DHCP server

WAC Switch

to BS

Session BorderController

WAC ServerWAC Server

AAA server

InternetWeb servers

Voice and VideoServices

AuxiliaryLANSwitch



OMC-R

WAC Server

WAC Switch

Router

Figure 16: FT WAC interconnections (case without HA)




5 WAC SERVER FUNCTIONAL ARCHITECTURE In the WAC Server, three main functional subsystems are identified as shown in Figure 17:

• The Session Control Function (SCF) sub-system. • The Data Transport Function (DTF) sub-system. • The Operation and Maintenance Function (OMF) sub-system.

SCF sub-system OMF sub-system

DTF sub-system

BS CN otherWAC OMC

Traffic

InternalControl

Figure 17: WAC Server functional architecture

5.1 Session Control Function The Session Control Function is in charge of managing the subscriber stations (SS) that are within radio coverage of a BS controlled by the WAC and that are involved in (or establishing) a session with the WiMAX network. Generally speaking, all functions needed for the end user management at RAN level are provided by the SCF sub-system. SS management includes as well the releases of the SS context upon detection of one of the following events: SS disconnection in case of pre-paid allowance exhausted. SS explicit de-registration from a BS. SS loss of radio coverage (implicit detection by e.g. inactivity detection in the BS, DHCP lease time expiration). As the system provides nomadicity and portability functions between cells, SS management also includes the handling of intra-WAC and inter-WAC mobility procedures. In such environment, location registration (for the SS in idle state) and paging procedures can be required. In this case SCF is in charge of providing them. SS management and SS location procedures rely on protocols on the different interfaces that are also part of the SCF sub-system.




5.2 Operation and Maintenance Function The Operation and Maintenance Function is in charge of setting and maintaining in operation the resources (Hardware and Software) used by the other sub-systems and plays the role of Agent in the interface with the management system (OMC-R or LMT) that plays the role of Manager. The functional areas covered by the OMF sub-system are the following :

• Configuration management : XML model for configuration parameters at Management system / WAC Server interface. Sub-systems internal (re)configuration under Management system control (e.g. at WAC Server start-up or in case of reconfiguration) or autonomously (e.g. at board insertion) with notification to the Management system.

• Software management (including SW migration) New SW version activation under Management system control. SW internal downloading (including pre-load for outage minimisation).

• Fault management : Sub-systems internal supervision. Alarm correlation, filtering and reporting to the Management system (and logging). Operational State change management and reporting to the Management system (and logging). Maintenance tests execution and reporting to the Management system.

• Performance management : Performance configuration (thresholds). PM counters collection and reporting to the Management system. PM based alarm generation and reporting to the Management system.

The system functions supported by the OMF sub-system include : • WAC Server initialisation

Reset/restart at WAC Server level. Reset/restart at board level.

• Synchronization management WAC Server sub-systems synchronization (Data, Faults, States ..). Data synchronization with the Management system.

• Communication management Secured communication services such as SSH/SFTP. Generic communication services such as TFTP. Internal WAC Server communication.

• Protection management Defence against HW failures (including boards and interfaces). Defence against SW failures.

• WAC Server Starting procedure control Booting and WAC IP address acquisition from a DHCP server. Connection to the Management system.




Setting of the security keys in the WAC Server. Initial SW downloading from the Management system.

5.3 Data Transport Function The Data Transport Function is the sub-system that provides all functions needed to transport data (traffic and control) between the WAC Server and the other Network Elements. Main functions include :

• Control data Between the WAC Server and the BS (BS control protocol and BS-WAC tunnels control protocol), Between the WAC Server and adjacent WAC Server (WAC Server control protocol), Between the WAC Server and the AAA Server (Authentication, Authorization and Accounting information) Between the local FA and the HA for macro-mobility,

• O&M data Between the WAC and the OMC,

• User data (SS traffic) WAC transparently routes SS traffic between the BS and Network Service Provider.

• QoS Management WAC processes DiffServ tagging at IP level and 802.1p tagging in case of Ethernet transport networks inside RAN (between BS and WAC)

• Security VPN tunnels management between the WAC and the CN.




6 INTERCONNECTION OF ACCESS CONTROLLER WITH OTHER NETWORK ELEMENTS

6.1 Interconnection of Access Controller with Base Stations The Access Controller is interconnected with the Base Stations through an aggregation network that provides for the necessary bandwidth and QoS. Two communication links are established between each BS and the WAC it is attached to as shown in Figure 18.

user's payload

GREHEADER

OUTER IPHEADER

GRE tunnel(s)

Control Plane

Data Plane

GREpacket

from/toBS

from/toWAC

INNER IPHEADER

control messagesBS Control Plane IP addressWAC RAN interface IP address

BS User Plane IP addressWAC RAN interface IP address

IP HEADER

DiffServ usercopy

Ethernet 802.1QHEADER

mapping

DiffServouter packet

802.1pouter frame

user's IP packettunneloverhead

L2

end-to-endlocal

Ethernet 802.1QHEADER

Figure 18: control plane and data plane between BS and WAC

Control plane communication link A certain quantity of service information flows between BS and WAC for control of users’ sessions, e.g.:




• Users’ Authentication/re-authentication requests. • QoS management. • Mobility handling. • Intra-WAC and inter-WAC mobility (micro and macro-mobility).

� Mobility is managed through BS to WAC user management information exchange. � Serving BS is informed by client of mobility intentions. BS informs WAC to prepare handover

to target BS. WAC prepares handover with the two BS. Eventually, the handover is performed. User plane communication link. User IP-based traffic is tunnelled between BS and WAC in GRE tunnels. This allows to use routers in aggregation network as only BS and WAC IP address need to be set in accordance with the aggregation network. Once authenticated and provided an IP address via DHCP, users are identified/managed within WAC via their IP address. BS and WAC have Ethernet interfaces. QoS tagging is provided at IP level(DiffServ DSCP) for end-to-end use, and locally at Ethernet level (802.1p) for direct use in case of an Ethernet aggregation network. TOS byte of user’s packet is copied in outer IP header (IP header of tunnel). Encryption in tunnel mode (IPSec ESP/GRE) can be added between the BS and WAC for the user plane. Without encryption, the MTU on the data plane is 1476 bytes.

6.2 Interconnection of WAC Server with other WAC Servers WAC Servers are interconnected for: • Inter-WAC mobility (handovers, Idle mode) • QoS communication in case of Network-assisted QoS (a central WAC is connected to SBC and relays

controls to other WACs Implementation is similar to that of BS-WAC communications both for control plane and data plane




6.3 Interconnection of Access Controller with Home Agent The Home Agent is necessary to address the users’ mobility. In this case Access Controller will act as a Proxy MIP (PMIP) on behalf of the client and as a Foreign Agent (FA) towards the Home agent. The users do not participate in the inter-WAC mobility which is transparent to them. It is the RAN infrastructure that handles the mobility for them. Figure 19 shows the case of a user that moves from BS A connected to WAC1 to BS B connected to WAC2. Traffic goes first through path1, then through path 2 and, eventually, through path 3. Handover to path 3 may be delayed until a current time-sensitive session is over. A GRE tunnel is established between WAC (FA function) and HA. The MTU is 1476 bytes.

Figure 19: Inter-WAC mobility

6.4 Interconnection of Access Controller with SBC Signalling plane between AC and SBC uses the IP address(es) of the Control Plane(s) on CN side.

END OF DOCUMENT

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