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Chapter 23 Voice
VMG8825-B Series User’s Guide
246
SIP User Agent
A SIP user agent can make and receive VoIP telephone calls. This means that SIP can be used for peer-
to-peer communications even though it is a client-server protocol. In the following figure, either
A
or
B
can act as a SIP user agent client to initiate a call.
A
and
B
can also both act as a SIP user agent to
receive the call.
Figure 148
SIP User Agent
SIP Proxy Server
A SIP proxy server receives requests from clients and forwards them to another server.
In the following example, you want to use client device
A
to call someone who is using client device C.
1
The client device (
A
in the figure) sends a call invitation to the SIP proxy server (
B
).
2
The SIP proxy server forwards the call invitation to
C
.
Figure 149
SIP Proxy Server
SIP Redirect Server
A SIP redirect server accepts SIP requests, translates the destination address to an IP address and sends
the translated IP address back to the device that sent the request. Then the client device that originally
sent the request can send requests to the IP address that it received back from the redirect server.
Redirect servers do not initiate SIP requests.
Содержание VMG8825-B Series
Страница 15: ...15 PART I User s Guide...
Страница 65: ...65 PART II Technical Reference...
Страница 204: ...Chapter 17 Home Connectivity VMG8825 B Series User s Guide 204 Figure 115 Network Setting Home Connectivity...
Страница 231: ...Chapter 23 Voice VMG8825 B Series User s Guide 231 Figure 139 VoIP SIP SIP Account Add new account Edit...
Страница 236: ...Chapter 23 Voice VMG8825 B Series User s Guide 236 Figure 141 VoIP SIP SIP Service Provider Add new provider Edit...
Страница 297: ...Chapter 40 Firmware Upgrade VMG8825 B Series User s Guide 297 Figure 182 Error Message...
Страница 313: ...313 PART III Appendices Appendices contain general information Some information may not apply to your device...
Страница 360: ...Index VMG8825 B Series User s Guide 360 Z ZyXEL Family Safety page 217...