B-28
Cisco Unified IP Phone 7960G and 7940G Administration Guide for Release 8.0 (SIP)
OL-7890-01
Appendix B SIP Call Flows
Call Flow Scenarios for Successful Calls
Figure B-10 Call Transfer with Consultation Using Failover
IP Network
SIP IP
Phone User B
IP
IP
2. 100 TRYING
3. 180 RINGING
4. 200 OK
11. 180 RINGING
12. 200 OK
13. ACK
2-way voice path
14. INVITE (a=sendonly)
15. 200 OK
16. ACK
17. REFER (Refer-To: C,
Replaces: B,Referred-By: B)
18. 501 NOT IMPLEMENTED
19. BYE(Also: C)
20. 200 OK
21. BYE
22. 200 OK
23. INVITE C (Requested-By: B)
24. 100 TRYING
25. 180 RINGING
26. 200 OK
27. ACK
2-way voice path
5. ACK
2-way voice path
User B presses transfer.
6. INVITE (a=sendonly)
7. 200 OK
8. ACK
9. INVITE C
10. 100 TRYING
1. INVITE
SIP IP
Phone User A
SIP IP
Phone User C
IP
137207
User B presses transfer.