Filter
Top Products
Appendix B SIP Call Flows
Call Flow Scenarios for Failed Calls
B-70
Cisco SIP IP Phone 7960 Administrator Guide
78-10497-02
Cisco SIP IP Phone-to-Cisco SIP IP Phone—Authentication Error
Figure B-18 illustrates an unsuccessful call in which User A initiates a call to
User B but is prompted for authentication credentials by the proxy server. User
A’s SIP IP phone then reinitiates the call with an SIP INVITE request that includes
it’s authentication credentials.
Figure B-18 Cisco SIP IP Phone-to-Cisco SIP IP Phone—Authentication Error
Proxy
Server
IP IP
2. 407 Authentication Error
4. Resend INVITE B
3. ACK
1. INVITE B
IP Network
SIP IP
Phone User A
SIP IP
Phone User B
41477