B-34
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-12 Network Call Forwarding (Busy)
IP
IP
11. 200 OK
5. INVITE B
9. 180 Ringing
10. 200 OK
13. ACK
8. INVITE C
6. 486 Busy Here
7. ACK
1. INVITE B
12. 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
41472
2-way RTP channel