本文件为规范和描述语言的正式使用建立了一套指南 （SDL）用于描述而非详细设计。它还为信息的使用提供了一些指导 序列图（MSC）、抽象语法符号1（ASN.1）和统一建模语言（UML） 与SDL合作。该准则的目的是为议定书标准报告员提供协助 ETSI交付物中出现的SDL是正式表达的，易于阅读和理解，并且具有一定的详细程度 与其他标准一致。本文件适用于所有使用SDL规定 任何类型的服务或行为。假设本文件的用户具备SDL的工作知识，必要时还具备MSC、ASN的工作知识。 1. 还有UML。本书不应被视为这些符号中的任何一种，而应与其他符号一起阅读 EG 201 383[1]，EG 201 015[2]和EG 201 872[3]。

The present document establishes a set of guidelines for the formal use of Specification and Description Language (SDL) for descriptive, rather than detailed design, purposes. It also provides some guidance on the use of Message Sequence Charts (MSC), Abstract Syntax Notation 1 (ASN.1) and the Unified Modeling Language (UML) when used in conjunction with SDL. The objective of the guidelines is to provide assistance to rapporteurs of protocol standards so that the SDL that appears in ETSI deliverables is formally expressed, easy to read and understand and at a level of detail consistent with other standards. The present document applies to all standards that make use of SDL to specify protocols, services or any other type of behaviour.Users of the present document are assumed to have a working knowledge of SDL and, where necessary, MSC, ASN.1 and UML. It should not be considered to be a tutorial in any of these notations and should be read in conjunction with EG 201 383 [1], EG 201 015 [2] and EG 201 872 [3].