B-18
Cisco SIP IP Phone Administrator Guide
Appendix B SIP Call Flows
Call Flow Scenarios for Successful Calls
Figure B-6
Cisco SIP IP Phone-to-Cisco SIP IP Phone Call Transfer without Consultation
IP Network
SIP IP
Phone User B
IP
IP
2. 100 TRYING
3. 180 RINGING
4. 200 OK
11. BYE
12. 200 OK
13. INVITE (Referred-By: B)
14. 100 TRYING
15. 180 RINGING
16. 200 OK
17. ACK
18. NOTIFY (Event: Refer)
19. 200 OK
2-way voice path
5. ACK
2-way voice path
User B presses blind transfer.
6. INVITE (c=0.0.0.0)
7. 200 OK
8. ACK
9. REFER (Refer-To: C,Referred-By: B)
10. 202 ACCEPTED
1. INVITE
SIP IP
Phone User A
SIP IP
Phone User C
IP
62503
User B dials user C.