General Information on Interconnecting with SIP Providers
From berofix - professional SIP gateway
When interconnecting an ISDN System with a SIP Service Provider several aspects of the communication flow need to be considered. During a call different phases of signalling occur and the call has multiple attributes.
The call/session phases are:
- call setup
- call connect
- call disconnect
During the call setup phase most attributes of the call are clear already. The most important attributes are typically:
- Destination Address Information
- Source Address Information
- Media Definition