ZyXEL Communications EX5501-B0 User Manual page 255

Figure 160 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.
In the following example, you want to use client device A to call someone who is using client device C.
Client device A sends a call invitation for C to the SIP redirect server (B).
1
The SIP redirect server sends the invitation back to A with C's IP address (or domain name).
2
Client device A then sends the call invitation to client device C.
3
Chapter 22 VoIP
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