As XML is independent of operating systems and programming languages, we use it to describe the structure of PDU and so heterogeneous systems can share one copy of XML descriptions.

• 1文件编译器可以被省去,以降低开发成本。 使用XML来描述协议中PDU的结构,XML与平台和语言无关,因此使用不同平台、不同编程语言的各个通信端可以共享一份XML描述。