论文部分内容阅读
抽象形式语法（ＡＳＮ．１）标注的网络协议数据单元可读性好，但是用传统的过程调用的方法去实现这些协议单元的编解码工作将是一件非常复杂而繁重的工作，文章使用面向对象的思想对抽象形式语法的基本数据类型进行封装，在对抽象形式语法标注的协议数据单元不作改动或稍作改动的情况下，直接利用原有的协议数据单元定义就完成这些协议数据单元的编解码工作，从而达到简化的目的。该文将重点叙述ＩＴＵ－Ｔ的抽象形式语法的对象封装，并以ＩＴＵ－Ｔ的Ｘ．６９１ ＰＥＲ编码作为例子来叙述抽象形式语法对象的编码方法是如何简化抽象形式语法所表示的协议数据单元的程序实现的。
However, it is a very complicated and arduous task to implement the codec work of these protocol units by using the traditional method of procedure call. This paper uses the method of oriented formalization (ASN.1) to read the network protocol data units. Object thinking encapsulates the basic data types of abstract formal grammar. If the protocol data unit marked by abstract formal grammar is unchanged or changed slightly, the original protocol data unit definition is used directly to complete these protocol data units Codec work, so as to achieve the purpose of simplification. This article will focus on the object encapsulation of ITU-T’s abstract formal syntax, and on the ITU-T’s X. The 691 PER encoding is taken as an example to describe how the encoding method of the abstract formal syntax object can be simplified by the procedure of the protocol data unit represented by the abstract formal syntax.