Cisco 7960 Administrator's Guide

Appendix B SIP Call Flows
Call Flow Scenarios for Failed Calls
B-58
Cisco SIP IP Phone 7960 Administrator Guide
78-10497-02
Call Flow Scenarios for Failed Calls
This section describes call flows for the following scenarios, which illustrate
unsuccessful calls:
•
Gateway-to-Cisco SIP IP Phone—Called User is Busy, page B-58
•
Gateway-to-Cisco SIP IP Phone—Called User Does Not Answer, page B-60
•
Gateway-to-Cisco SIP IP Phone—Client, Server, or Global Error, page B-63
•
Cisco SIP IP Phone-to-Cisco SIP IP Phone—Called User is Busy, page B-66
•
Cisco SIP IP Phone-to-Cisco SIP IP Phone—Called User Does Not Answer,
page B-68
•
Cisco SIP IP Phone-to-Cisco SIP IP Phone—Authentication Error, page B-70
Gateway-to-Cisco SIP IP Phone—Called User is Busy
Figure B-13 illustrates an unsuccessful call in which User A initiates a call to
User B but User B is on the phone and is unable or unwilling to take another call.
Figure B-13 Gateway-to-Cisco SIP IP Phone—Called User is Busy
IP
3. Call Proceeding
6. Disconnect (Busy)
1. Setup
7. Release
PBX A
User A
GW1 IP Network
4. 100 Trying
5. 486 Busy Here
8. ACK
2. INVITE
9. Release Complete
41725
SIP IP Phone
User B

Cisco 7960 Specifications

General

Codecs	G.711, G.729a
Protocol Support	SCCP, SIP
Ethernet Ports	2 x 10/100 Ethernet ports
Power Options	Power over Ethernet (PoE), AC adapter
Audio	Full-duplex speakerphone
Buttons	6 line buttons
Weight	3.5 pounds