P-2602H(W)(L)-DxA Series User’s Guide
11.2.1.2 SIP Service Domain
The SIP service domain of the VoIP service provider is the domain name in a SIP URI. For example, if the SIP address is
11.2.2 SIP Call Progression
The following figure displays the basic steps in the setup and tear down of a SIP call. A calls B.
Table 52 SIP Call Progression
A | B |
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1. INVITE
2. Ringing
3. OK
4. ACK
5.Dialogue (voice traffic)
6. BYE
7. OK
A sends a SIP INVITE request to B. This message is an invitation for B to participate in a SIP telephone call.
6B sends a response indicating that the telephone is ringing.
7B sends an OK response after the call is answered.
8A then sends an ACK message to acknowledge that B has answered the call.
9Now A and B exchange voice media (talk).
10After talking, A hangs up and sends a BYE request.
11B replies with an OK response confirming receipt of the BYE request and the call is terminated.
11.2.3 SIP Servers
SIP is a
When you use SIP to make a VoIP call, it originates at a client and terminates at a server. A SIP client could be a computer or a SIP phone. One device can act as both a SIP client and a SIP server.
152 | Chapter 11 Voice |