HP FlexNetwork MSR Series Configuration Manual page 147

Figure 38 Call setup procedures involving a proxy server
This is a simplified scenario where only one proxy server is involved and no registrar is present. A
complex scenario, however, might involve multiple proxy servers and registrars.
Call redirection
Figure 39, when a SIP redirect server receives a session request, it sends back a
As shown in
response indicating the address of the called SIP endpoint instead of forwarding the request. The
calling and called endpoints send request and response to each other directly.
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