Users Manual Part 2

Chapter 22 Voice

EMG6726/8726-B10A User’s Guide

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Figure 151 SIP Call Through Proxy Servers

The following table shows the SIP call progression.

1 User Agent 1 sends a SIP INVITE request to Proxy 1. This message is an invitation to User Agent 2 to

participate in a SIP telephone call. Proxy 1 sends a response indicating that it is trying to complete the

request.

2 Proxy 1 sends a SIP INVITE request to Proxy 2. Proxy 2 sends a response indicating that it is trying to

complete the request.

3 Proxy 2 sends a SIP INVITE request to User Agent 2.

Table 101 SIP Call Progression

UA 1 PROXY 1 PROXY 2 UA 2

Invite

100 Trying Invite

100 Trying

180 Ringing

200 OK

ACK

RTP RTP

BYE

200 OK

DSL