Prestige 2602HW Series User’s Guide
9.2.1.2 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
The following figure displays the basic steps in the setup and tear down of a SIP call. A calls B.
Table 32 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
1A sends a SIP INVITE request to B. This message is an invitation for B to participate in a SIP telephone call.
2B sends a response indicating that the telephone is ringing.
3B sends an OK response after the call is answered.
4A then sends an ACK message to acknowledge that B has answered the call.
5Now A and B exchange voice media (talk).
6After talking, A hangs up and sends a BYE request.
7B replies with an OK response confirming receipt of the BYE request and the call is terminated.
9.2.3SIP ServersSIP 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.
132 | Chapter 9 Introduction to VoIP |