Cisco SIP IP Phone - Page 120

B-10
Cisco SIP IP Phone Administrator Guide
AppendixB SIP Call Flows
Call Flow Scenarios for Successful Calls
Figure B-4 Cisco SIP IP Phone-to-Cisco SIP IP Phone Call Hold with Consultation
IP IP IP
2. 180 Ringing
3. 200 OK
2-way RTP channel
A is put on hold. The RTP channel between A and B is torn down.
4. ACK
2-way RTP channel
B is disconnected from C.
A is taken off hold. The RTP channel between A and B is reestablished.
5. INVITE (c=IN IP4 0.0.0.0)
6. 200 OK
7. ACK
14. INVITE (c=IN IP4 IP-User B)
15. 200 OK
16. ACK
1. INVITE B
9. 180 Ringing
10. 200 OK
8. INVITE C
13. 200 OK
12. BYE
11. ACK
IP Network
SIP IP
Phone User A
SIP IP
Phone User B
SIP IP
Phone
User C
41466