B-40
Cisco SIP IP Phone Administrator Guide
Appendix B SIP Call Flows
Call Flow Scenarios for Successful Calls
Figure B-12 Cisco SIP IP Phone-to-Cisco SIP IP Phone Network Call Forwarding (No Answer)
IP
IP
13. 200 OK
7. 180 Ringing
5. INVITE B
9. 200 OK
12. 200 OK
11. 180 Ringing
15. ACK
10. INVITE C
8. CANCEL
6. 180 Ringing
1. INVITE B
14. ACK
3. 300 Multiple Choices
2. INVITE B
4. ACK
IP Network
SIP IP
Phone
User A
SIP IP
Phone
User B
SIP IP
Phone
User C
Proxy
Server
Redirect
Server
IP
41473
2-way RTP channel