Yealink SIP-T38G

Appendix
341
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 the 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 Proxy Server User B
F1. INVITE B
F2. INVITE B
F3. 100 Trying
F9. ACK
F10. ACK
F5. 180 Ringing
2-way RTP channel established
F8. 200 OK
F7. 200 OK
F6. 180 Ringing
F4. 100 Trying
F11. BYE
F12. BYE
F13. 200 OK
F14. 200 OK