Yealink SIP-T2XP Administrator's Manual page 550

Administrator's Guide for SIP-T2xP IP Phones
SIP 2xx—Successful Responses
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SIP 3xx—Redirection Responses
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SIP 4xx—Client Failure Responses
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SIP 5xx—Server Failure Responses
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SIP 6xx—Global Failure Responses
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The following figure illustrates the scenario of a successful call. In this scenario, the two
end users are User A and User B. User A and User B are located at Yealink SIP IP
phones.
The call flow scenario is as follows:
1. User A calls User B.
2. User B answers the call.
3. User B hangs up.
User A
532
Proxy Server
F1. INVITE B
F4. 100 Trying
F6. 180 Ringing
F8. 200 OK
F9. ACK
2-way RTP channel established
F12. BYE
F13. 200 OK
User B
F2. INVITE B
F3. 100 Trying
F5. 180 Ringing
F7. 200 OK
F10. ACK
F11. BYE
F14. 200 OK