电信VOIP计费系统方案,在全国各地应用.-VOIP Telecom Billing System program, the application throughout the country.

标准sip的ＲＦＣ３２６１文档，是开发基于sip的voip通信方案的必备手册.对其中的重点部分用红色进行了标记-Sip the RFC3261 standard documents, the development of voip in sip-based communications program manual required. The focus of some of them were marked in red