一、 dx200 platform

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一、 DX200 Platform

§1.1 DX200 Platform: Nokia’s proven DX 200 platform supports

the switching of traffic channels (speech), user data, signalling, short messages and the functions required for cellular radio administration.

In addition to the GSM network, the DX200 also forms the basis for the Nokia NMT, PMR, PSTN and ISDN products.

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DX200 Platform

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DX 200 structure in block diagram

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§1.2 DX200 Hardware: 1. Racks:

2. Sub-racks:

3. Cartridges:

4. Units:

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§1.3 Power Supply:

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§1.3 Power

Supply:

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§1.4 Computer Units:

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§1.5 Redundancy Principles:

- 2N:

When two units are dedicated to a task to which one is enough at any given time, one of the units is always active or in the working state (WO). The other unit is kept in the hot stand-by state or the spare (SP) state.

- N+1:

When there is just one or a few spare units for a set of N units of a given type, the spare unit is not used by the applications and is not permanently bound to some of the N active units but can take over the load of any one of them in case of an active unit failure or by an operator command.

2n

n+1

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§1.6 Functional Unites: 1. Network interface, ET: Access: - electrical synchronisation - adaptation of external 2Mbit/s

2. Group Switch, GSW : Switches: - dynamic connections(calls and data) - signalling

- internal semipermanent connections

3. Control functionality : - call control

- controls and supervises GSW - connects / releases all connections

- performs tests in the switching network - hunts free circuits MCMU/BCSU in BSC, SWM in HLR, SCU in SXC

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4. Clock and Synchronisation Unit, CLS : - hierarchical/plesiochronous mode, changes the mode automatically

- the synchronisation signal comes from ETs in hierarchical mode

- generates the synchronisation signals

5. Message Bus, MB : - link between computer units

6. Operation and Maintenance Unit, OMU: - interface between the system and the user

- monitors : configuration and alarms in the system

- connects I/O-devices

- local mass storage for SW back-ups

- connections to the OMC in BSC

- non-redundant or 2N redundant

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二、 I/O System

§2.1 Introduction :

1. I/O system： consists of software and peripheral devices .

2. I/O system： located in the operation and maintenance unit (OMU).

3. I/O system： provides with all the necessary I/O-services by the MMI system.

§2.2 I/O Devices:

1. Mass memories:

- WDU: winchester disk unit

- FDU : floppy disk unit

- FDU : magneto-optical disk

- CTU : cartridge tape unit

- MTU : magnetic tape unit

2. User interface:

- LPT : line printer

- VDU: visual display unit

I/O Devices

DX 200

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DX 200 DX 200DX 200

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二、 I/O System

3. Virtual devices: - VTP : virtual terminal protocol - VPP : virtual printer protocol - VDS : virtual data storage 4. Special I/O devices: - BBU : byte basket unit - COK : command calendar - DIA : dialog

§2.3 Working states of I/O Devices: 1. View I/O devices ( ZISI ): WO (working): - WO-BU: working busy - WO-ID: working idle - WO-CL: working closing BL (blocked): - BL-SY: blocked by system - BL-US: blocked by user

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二、 I/O System TE (test): - TE-ID : test idle ……no test is running - TE-AC: test active ……test is running MI (missing): - MI-SY: missing by system ……HW missing - MI-US: missing by user ……state set by user 2. WDU & FDU: - MI-SY: when no hardware is equipped - BL-SY: hardware is faulty and the disk drive is not in working condition - WO-ID: all except user operations to the disk drive are prevented - WO-BU: normal operation. 3. VDU & LPT: - MI-SY: when no hardware is equipped - BL-SY: when hardware is equipped, but is OFFLINE or the plug-in unit is faulty - WO-ID: when the device is ONLINE 4. CTU & MTU: - MI-SY: when no hardware is equipped or tape unit is not powered - BL-SY: hardware is faulty, busy or not ready (offline) - WO-ID: tape unit is online and tape is loaded - WO-BU: normal operation state, tape file is opened and data can be stored on tape - TE-ID: tape unit is detected to be faulty or prepared to be diagnosed by command

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二、 I/O System

§2.4 Units:

1. WDU, Hard disks contain for example:

- program blocks of different computer units

- back-up copies of files containing permanent or semipermanent data

- MML programs and menus.

2. VDS, Virtual Data Storage :

- used in the data transfer of the FTAM protocol. (not DX200 format)

- changes the data files to another format before storing it from the disks.

§2.5 Logical files:

1. List logical files: Displays all logical files of OMU that are connected to LPT-1:

< ZIIL:,OMU:DEV=LPT-1;

http://127.0.0.1:41403/s10_5e/NED?action=retrieve&identifier=mmliil&edition=5&language=en&coverage=global&encoding=xhtml_1_0&component=data&item=data&pointer=cmdiil#cmdiil

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二、 I/O System

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二、 I/O System

2. Modify/change/delete the connections by a device: < ZII? ? ..... DISPLAY MENU D: ..... DISPLAY INFORMATION OF GIVEN LOGICAL FILE S: ..... CHANGE OBJECT CONNECTED TO LOGICAL FILE L: ..... LIST LOGICAL FILES CONNECTED TO GIVEN OBJECT C: ..... CHANGE OBJECT TO ANOTHER IN ALL LOGICAL FILES F: ..... CREATE LOGICAL FILE P: ..... CREATE SPARE LOGICAL FILE R: ..... REMOVE LOGICAL FILE I: ..... LINK PHYSICAL DISK FILE TO LOGICAL FILE G: ..... CHANGE SIGNALLED PROCESS Z; ..... RETURN TO MAIN LEVEL

§2.5 Logical file type: Logical files are transit files between application programs and I/O devices .

1. Permanent logical files: - user cannot delete or change the name - can change the connections - connections are stored on disk

2. Semipermanent logical files: - created and deleted by the user

3. Temporary logical files: - deleted immediately after the MML session is over

http://127.0.0.1:41403/s10_5e/NED?action=retrieve&identifier=dn9763965&edition=13&language=en&coverage=global&encoding=xhtml_1_0&component=data&item=data&pointer=id01896#id01896

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三、 File Administration

§3.1 DX200 software:

1. System software:

- The operating system (OS) is the software core and interfaced with the CPU.

- Divided into three different levels: system, service, program blocks

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2. Operating system: The main services of the operating system (DMXRTE) can be divided into the

following function groups:

- processor time scheduling

- message transfer

- real time services

- handling of processes and process families

- supervision services

The processor time is allocated according to the priority of the process.

The main states of a process

and possible changes

between them.R E A D Y T O R U N R U N N IN G

W A IT

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三、 File Administration§3.2 DX200 file system: 1. File types: DX 200 disk files can be divided into two main categories: data files and

Software files.

Data files:

- Configuration files: contain network element specific data, which can be modified with MML commands. Configuration files are saved and actively used in the memory of the computer units.

- Work files: are created and updated by the applications, and they are used only in the memory of the computer units.

- Ring files: are files where the new data is written on the top of the old data. An example of a ring file is the alarm history file. Ring files are stored on hard disks (WDUs)

Software files:

- Program code files: are used in the memory of the microcomputer units, and the backup copies are also on the hard disks.

- MML program files: are stored on hard disks. They are loaded into the RAM of the OMU during the MML session.

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三、 File Administration 2. Disk files: The main level on disk directory structure is the root directory. In the

SCMANA subdirectory there is located e.g. SOMAFI file which stores all the information about created SW-packages. Under the package directories are stored all subdirectories which belong to the SW-package (BLCODE, MMDIRE, LFILES, CONVPR, ASWDIR).

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三、 File Administration (BLCODE, MMDIRE, LFILES, CONVPR, ASWDIR).

BLCODE :

- contains the program code files which are loaded to the memories of the microcomputer during the start up phase. The master file of the system is MAFILE in the BLCODE subdirectory. The MAFILE contains information about all the load modules within the SW build.

MMDIRE:

- contains the MML program code files, MML text files and menus.

LFILES :

- contains the back up copies of data files, the preprocessor code and data files.

CONVPR :

- contains the conversion programs which might be needed during a major SW update.

ASWDIR :

- can be used for storing macros. The system itself constructs the necessary directory and files for measurements. Also, when installing a change delivery, the CFLIST file is copied into the ASWDIR directory.

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三、 File Administration 3. Disk file handling: The commands for disk file handling: ZIWX / ZIWY / ZIBC

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三、 File Administration§3.3 Loading system and unit restarts: 1. Loading concepts: Initial loading:

- When the unit is restarted, the load modules contain the program code and configuration files. The loading source is determined by the maintenance procedures or by user. The source can be a hard disk or local memory (codes and files already residing in the memory) so the working unit of the same

type. Primary copy is needed in the case of configuration files.

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三、 File Administration File loading:

- If the target file does not exist when the loading is started, the file is created with the same structure as the source file.

Distribution:

- The distribution is a transaction in which the modification of the data of one file is taken into the copies of the data concerned in the other units of the exchange. The distribution is carried out from the primary copy to the read-only copies.

Warming:

- means the updating of work files from the active unit. Warming is needed because of a hot stand-by system. Spare unit is always updated in the case of units which use 2n redundancy because the spare unit knows that there is only one unit which to follow. Spare is “cold” for units using n+1 redundancy because it is not known in advance which unit to replace.

2. Loading sources: - OMU hard disk (WDU)

- Active unit of the same type

- Primary unite the active unit

- Own unit

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三、 File Administration 3. Restarts: Restarts can be caused by several different reasons.

Unit state change causes a restart in the following state change combinations: SE to TE, TE to SP and TE to WO. (ZUSC)

Session 2 Online Caps Lock Num

DX 200 SERVICE TERMINAL MAIN LEVEL COOMANDS:

? ..... MENU / HELP A ..... ANALYSER L ..... EXTENSION HANDLING B ..... DEFINE ENVIROMENT O ..... OPERATING SYSTEM COMMANDS C ..... COMMAND LANQUAGE UTILITIES R ..... REMOTE DEBUGGER HANDLING D ..... MEMORY AND I/O HANDLING S ..... SYSTEM MONITORING COMMANDS E ..... EXIT DEBUGGER SESSION T ..... SET/DISPLAY TERMINAL TYPE I ..... GENERAL INFORMATION W ..... WS-220 FILE TRANSFER UTILITY

INITIAL NAME: 00BE 0000 00 CURRENT NAME: 00BE 0000 00

00-MAN>

User: Reset button

User: Serviceterminal

System: Recovery

User: MML terminal

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三、 File Administration 4. Restart type: Restart (Hot) with MML commands (ZUSU).

- The types of unit restart (values for R-parameter):

WRM (warm): Code and files are loaded at unit restart (default).

HOT : Code and files are not loaded at unit restart. Only the file buffers are reset, and the applications start from the beginning.

MIN (mini):The restart of the exchange is imperfect as only disk services and some parts of other service blocks are activated, such as maintenance and file system. E.g. databases are not loaded. The mini restart should not be initiated for non-database units.

- The alternative loading modes :

OPT (optimal): Only the code whose checksum has changed is loaded (default). The data files whose checksums have changed or files which do not have a checksum are loaded.

TOT (total): All initially loadable program blocks and data files are loaded (default value) by using the normal sources.

DSK (disk): All initially loadable program blocks are loaded from the disk of the OMU. This parameter can be used for example in change note installation.

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- The file loading modes :

VIRT (virtual): Files will be loaded virtually, that is, in the background.

IMM (immediately): All files are loaded immediately.

Restart (Warm) with the reset button: The code is not loaded unless there is a checksum error. Files are loaded from the primary unit.

Restart (Cold) by power cut: The code will be loaded from the disk, and the data files are loaded from the primary unit. Cold restart can be initiated either for a unit or for the whole system.

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三、 File Administration 5. Unit states:

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四、Maintenance§4.1 Supervision & Maintenance in the DX 200 solution :

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四、Maintenance§4.2 Detection and collection of alarm :

- Wired alarms (=hardware alarms)

- Trunk circuit alarms (=ET alarms, line alarms)

- Software alarms (=alarms detected by software)

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四、Maintenance§4.3 Types of alarms :

- Notices: are additional information about the situation in the exchange.

- Disturbances(:are used for informing about temporary disturbance situations.

Notices and disturbances (*) do not require actions from the user.

- Alarms: can be cancelled in two ways: automatically by the alarm system or by a user with MML commands. (* / ** / ***)

- Error ratio counters: are used for observing events that happen repeatedly. Each error ratio counter has two sides: one side for all events and one side

for failed events.

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四、Maintenance§4.4 Alarm system user interface :

1. Alarm system can be handled by the user with MML commands: < ZA?

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四、Maintenance 2. Alarms printouts:

一、 dx200 platform

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