SIP

1. Difference Between INVITE and re-INVITE difference

    INVITE has no To tag

    re-INVITE has To tag

2. MRF

    conference, code translation and collect data

    媒体资源功能 由IMS定义 用来提供媒体处理服务，例如会议，代码转换与提示/收集等。

3. autoscape 测试case