B-26
Cisco SIP IP Phone Administrator Guide
Appendix B SIP Call Flows
Call Flow Scenarios for Successful Calls
Figure B-8
Cisco SIP IP Phone-to-Cisco SIP IP Phone Call Transfer with Consultation
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 (c=0.0.0.0)
15. 200 OK
16. ACK
17. REFER (Refer-To: C,
Replaces: B,Referred-By: B)
18. 202 ACCEPTED
19. INVITE (Referred by: B, Replaces: B)
20. 200 OK
21. ACK
22. BYE
23. 200 OK
24. NOTIFY (Event: Refer)
25. 200 OK
26. BYE
27. 200 OK
2-way voice path
5. ACK
2-way voice path
User B presses transfer.
6. INVITE (c=0.0.0.0)
7. 200 OK
8. ACK
9. INVITE C
10. 100 TRYING
1. INVITE
SIP IP
Phone User A
SIP IP
Phone User C
IP
62501
User B presses transfer.