Cisco 7960G Administrator's Manual page 124

Call Flow Scenarios for Successful Calls
Figure B-10 Call Transfer with Consultation Using Failover
SIP IP
Phone User A
IP
1. INVITE
2. 100 TRYING
3. 180 RINGING
4. 200 OK
5. ACK
2-way voice path
6. INVITE (c=0.0.0.0)
7. 200 OK
8. ACK
17. REFER (Refer-To: C,
Replaces: B,Referred-By: B)
18. 501 NOT IMPLEMENTED
19. BYE(Also: C)
20. 200 OK
23. INVITE C (Requested-By: B)
24. 100 TRYING
25. 180 RINGING
26. 200 OK
27. ACK
2-way voice path
Cisco SIP IP Phone Administrator Guide, Release 6.x and 7.x
B-28
SIP IP
Phone User B
IP Network
IP
User B presses transfer.
9. INVITE C
10. 100 TRYING
11. 180 RINGING
12. 200 OK
13. ACK
User B presses transfer.
2-way voice path
14. INVITE (c=0.0.0.0)
15. 200 OK
16. ACK
21. BYE
22. 200 OK
Appendix B
SIP IP
Phone User C
IP
SIP Call Flows