> Mobile radio interface signalling layer 3; General aspects
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## 目录 / Contents
1. [范围 / Scope](#1-范围--scope) 2. [参考文献 / References](#2-参考文献--references) 3. [定义和缩略语 / Definitions and abbreviations](#3-定义和缩略语--definitions-and-abbreviations) 4. [介绍 / Introduction](#4-介绍--introduction) 5. [层3功能结构 / Structure of layer 3 functions](#5-层3功能结构--structure-of-layer-3-functions) 6. [协议架构 / Protocol architecture](#6-协议架构--protocol-architecture)
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范围 / Scope
中文说明
本文件定义了GSM Um接口（即3GPP系统中移动台与网络之间的接口）第3层及其子层的主要架构。对于CM子层，描述仅限于典型示例、非GPRS业务的呼叫控制、补充业务和短消息业务。本文件还定义了第3层协议所采用的基本消息格式和错误处理。
对于CTS业务，本文件定义了GSM Um*接口（即CTS capable移动台(CTS-MS)与固定台(FP)之间的接口）第3层的主要架构。
相应的协议在其他技术规范中定义，见第4.3.4条。
对于非GPRS业务，子层与相邻层之间的通信以及子层所提供的服务通过抽象服务原语进行描述。但本文件仅对描述所产生的外部可观察行为进行规范性规定。
对于GPRS业务此外，本文件的信息性附件C中还包含了子层之间本地信息传递和刺激的说明。
本文件还定义了EPS NAS和5GS NAS第3层协议及其子层的主要架构，包括第3层所采用的消息格式。
在本文件中，MS也用作UE的同义词。
第6至10条的描述未被主动维护。
English
1 Scope
The present document defines the principal architecture of layer 3 and its sublayers on the GSM Um interface, i.e. the interface between Mobile Station (MS) and network; for the CM sublayer, the description is restricted to paradigmatic examples, call control, supplementary services, and short message services for non-GPRS services. It also defines the basic message format and error handling applied by the layer 3 protocols.
For CTS services, the present document defines the principal architecture of layer 3 on the GSM Um* interface, i.e. the interface between a CTS capable Mobile Station (CTS-MS) and a Fixed Part (FP).
The corresponding protocols are defined in other Technical Specifications, see clause 4.3.4.
For non-GPRS services the communication between sublayers and adjacent layers and the services provided by the sublayers are distributed by use of abstract service primitives. But only externally observable behaviour resulting from the description is normatively prescribed by the present document.
For GPRS services in addition the local information transfer and stimuli sent between sublayers is informatively included within Annex C of in the present document.
This document also defines the principal architecture of the EPS NAS and 5GS NAS layer 3 protocol and their sublayers, including the message format applied by layer 3.
In the present document MS is also used as a synonym for UE.
Descriptions in clauses 6 to 10 are not maintained actively.
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参考文献 / References
中文说明
以下文档中的条款通过引用而构成本文件的条款。
- 参考文献可以是特定的（通过出版日期、版号、版本号等标识），也可以是非特定的。 - 对于特定引用，后续修订不适用。 - 对于非特定引用，应适用最新版本。在引用3GPP文档（包括GSM文档）时，非特定引用隐含地指本文件同一版本中的最新文档。
（完整参考文献列表见原始协议文档）
English
2 References
The following documents contain provisions which, through reference in this text, constitute provisions of the present document.
- References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific. - For a specific reference, subsequent revisions do not apply. - For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same Release as the present document.
(Full reference list available in original protocol document)
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定义和缩略语 / Definitions and abbreviations
中文说明
3.1 定义
本文件适用的术语和定义见3GPP TR 21.905 [1a]。
3.2 缩略语
本文件适用的缩略语见3GPP TR 21.905 [1a]及以下规定：
English
3.1 Definitions
For the purposes of the present document, the terms and definitions given in 3GPP TR 21.905 [1a] apply.
3.2 Abbreviations
For the purposes of the present document, the abbreviations defined in 3GPP TR 21.905 [1a] and the following apply:
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介绍 / Introduction
中文说明
（待续）
English
(To be continued)
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层3功能结构 / Structure of layer 3 functions
中文说明
（待续）
English
(To be continued)
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协议架构 / Protocol architecture
中文说明
（待续）
English
(To be continued)
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## 交叉引用 / Cross References
- Layer 3 (L3) - 信令层3 - NAS - 非接入层 - Service Primitive - 服务原语 - TS 24.008 - 移动性管理和呼叫控制 - TS 24.301 - EPS NAS协议 - TS 24.501 - 5G NAS协议