User's Manual

Chapter 21 Voice 184

2 The

SIP proxy server forwards the call invitation to C.

Figure 114 SI

P Proxy Server

SIP Redirect Server

A SIP redirect server accepts SIP requests, translates the destination addr

ess 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

1 C

lient device A sends a call invitation for C to the SIP redirect server (B).

2 Th

e SIP redirect server sends the invitation back to A with C’s IP address (or domain name).