GSM BSS 信令消息诠释-位置更新流程

GSM BSS信令消息诠释 ——位置更新流程

GSM BSS信令消息诠释－位置更新流程

目录

位置更新流程信令消息诠释 .......................................................................................................... 4

1. 信令流程 .................................................................................................................................4 2. 信令流程详解 ..........................................................................................................................4

(1).

(2). (3). (4). (5). (6). (7). (8). (9). (11). (12). (13). (14). (15).

Channel Request ......................................................................................................4 Channel Required .....................................................................................................7 Channel Activation ....................................................................................................7 Channel Activation Acknowledge .............................................................................9 Immediate Assignment Command......................................................................... 10 SABM(Set Asynchronous Balanced Mode)帧 ....................................................... 13 UA(Unnumbered Acknowledgement)帧 ................................................................ 14 Establish Indication ................................................................................................ 14 CR(Call Request)(CMP L3 Information) ................................................................ 17 Location Updating Accept ...................................................................................... 19 Location Updating Reject ....................................................................................... 19 TMSI Reallocation Complete ................................................................................. 20 Clear Command ..................................................................................................... 20 Clear Complete ...................................................................................................... 20

(10). CC（Call Confirm） ............................................................................................... 19

附录1：Element Identifier .......................................................................................................... 21

9.3 Other Information Elements ................................................................................................ 21

9.3.1 Channel Number ...................................................................................................... 22 9.3.2 Link Identifier ............................................................................................................ 23 9.3.4 BS Power ................................................................................................................. 25 9.3.5 Channel Identification ............................................................................................... 25 9.3.6 Channel Mode .......................................................................................................... 25 9.3.7 Encryption information ............................................................................................. 27 9.3.8 Frame Number ......................................................................................................... 28

附录2：MS Power Class and Level .......................................................................................... 28

4.1 Output power ....................................................................................................................... 29

4.1.1Mobile Station............................................................................................................ 29

附录3：Channel Description ....................................................................................................... 1 附录4：Message Type ................................................................................................................ 7

10.4 Message Type ..................................................................................................................7

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GSM BSS信令消息诠释－位置更新流程

附录5：Data Link Layer Structure ............................................................................................. 12 5 Overview of Data Link Layer Structure ................................................................................... 12

5.1 Functional Composition ...................................................................................................... 12 5.2 Identification of Data Link End Points ................................................................................. 13 5.3 Data Link Procedure ........................................................................................................... 14 5.4 Data link Distribution Procedure ......................................................................................... 14 5.5 Random Access Procedures .............................................................................................. 14

6 Specific Requirements ............................................................................................................ 15

6.1 Mode of Operation and Allowed SAPIs .............................................................................. 15 6.2 Acknowledged Mode of Operation...................................................................................... 15

6.2.1 Window Size............................................................................................................. 15

6.2.2 Processing Capacity ................................................................................................ 15

附录6：CKSN(Ciphering Key Sequence Number) ................................................................... 16 附录7：Location Updating Type................................................................................................ 17 附录8：Classmark ..................................................................................................................... 18 附件9：IMSI/TMSI ..................................................................................................................... 27 附件10：信令跟踪文件 .............................................................................................................. 28 FAQ：如何下载GSM协议？ ..................................................................................................... 29

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GSM BSS信令消息诠释－位置更新流程

GSM BSS信令消息诠释－位置更新流程

骆瑛（162429）

关键词：位置更新 协议 信令

摘 要：信令就如同设备之间的语言，设备之间的正常运行都是建立在这种语言也就是信令的正常交互基础之上的。正如不同的国家使用不同的语言，不同的语言又使用不同的语法一样，在通信网中，不同的接口使用不同的信令，不同的信令又对应使用不同的协议。因此信令是建立在协议基础之上的，而读懂了信令就读懂了设备之间的语言，就能清楚的明白系统是如何进行通讯的，特别当有故障出现但却没有任何告警提示信息时，信令分析就成为了排障最高效的方法。

本文以位置更新信令流程为例，结合不同接口的协议，从字节级深入解读每条信令里的核心字段，使读者很容易理解每条信令的功能和作用，进而理解掌握整个位置更新信令流程的意义所在；为通过分析信令定位、解决相关网络问题奠定扎实的基础；同时也掌握了如何有效的使用协议来帮助解读信令的方法。 参考资料清单： 0408协议 0808协议 0858协议

BSS信令与接口分析基础 M900／M1800 BSS 信令分析手册 3G鉴权加密特性描述

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