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[多选题]
SIP网络中对UAC和UAS的描述哪些是正确的()。
A.UAC发送SIP请求
B.UAS发送SIP请求
C.UAS返回响应
D.UAC返回响应
查看答案
![](https://static.youtibao.com/asksite/comm/h5/images/solist_ts.png)
A.UAC发送SIP请求
B.UAS发送SIP请求
C.UAS返回响应
D.UAC返回响应
A.UAC负责发起SIP呼叫请求
B.UAS负责对呼叫请求作出响应
C.UAS负责发起SIP呼叫请求
D.UAC负责对呼叫请求作出响应
A.UAS/UAC
B.PROXY Server
C.Location Server
D.Redirect Server
A.UAC
B.ProxySever
C.ProxyServerorRedirectServer
D.RedirectServer
E.LocationServer
A.pending
B.complete
C.ack
D.request
A.17userbusy
B.18nouserresponding
C.19noanswerfromtheuser
D.20subscriberabsent