SIP call setup with authentication

This call flow shows the SIP call setup between a SIP client (192.168.0.10) and a SIP server (216.234.64.8). The flow also shows the RTP message flow between the SIP client and the Media Gateway (216.234.64.16).
The example covers the following:

1. SIP invite from the client.
2. The SIP server challenges the client to authenticate.
3. The client responds to the authentication challenge.
4. The call is connected.
5. The call enters the conversation phase with RTP traffic.
6. The SIP call is cleared.

SIP invite handling