Successful Call Setup And Call Hold - Yealink SIP-T2XP Administrator's Manual

Administrator's Guide for SIP-T2xP IP Phones

Successful Call Setup and Call Hold

The following figure illustrates a successful call setup and call hold. 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 A places User B on hold.
User A
F9. INVITE B (sendonly)
410
Proxy Server
F1. INVITE B
F4. 180 Ringing
F6. 200 OK
F7. ACK
2-way RTP channel established
F12. 200 OK
F13. ACK
No RTP packets being sent
F2. INVITE B
F3. 180 Ringing
F5. 200 OK
F8. ACK
F10. INVITE B (sendonly)
F11. 200 OK
F14. ACK
User B