In this section you learned:
- All calls are managed by a set of procedural messages between the network
and the user
- These are all carried via the D channels at either end
- The end-to-end connection for the call itself is set up on the B Channel
- The most important messages are SETUP and DISC.
- Disconnections are accompanied by a cause code which will reveal why the
call terminated
- Procedures also exist to manage multiple devices attempting to answer
incoming calls
- Devices sharing a BRI do not cooperate with each other, they communicate
with the network