HP-UX C SIP Stack Programmer's Guide (Novembery 2007)

10 HP-UX C SIP Stack Programmer’s Guide
Entity Interaction
6. Bob picks up the call and the UA2 sends a 200 (OK) message
to the calling UA. This message also contains a packet
describing the media capabilities of Bob’s terminal.
7. UA1 sends an ACK request to confirm the 200 (OK) response
was received.
S
ESSION TERMINATION The session termination call flow proceeds as follows:
1. The caller decides to end the call and “hangs-up”. This results
in a BYE request being sent to UA2.
2. UA2 responds with 200 (OK) message and notifies Bob that
the conversation has ended.
CALL REDIRECTION Figure 1-2 below shows a simple call redirection scenario.
Figure 1-2 Simple Call Redirection Using a Redirect Server
User Agent
1
User Agent
2
1: INVITE bob@
acme.com
a.toon.com gw.telco.com
Redirect
Server
sip.acme.com
Location
Service
2:
bob@
acme.com ?
3:
3573572@
gw.telco.com
6: INVITE [e-mail]
4: 302/
Moved temporarily
contact: 3573572@
gw.telco.com
7: 200/OK
5: ACK
8: ACK