SLS can only process calls while it is in the Registered state in which it performs the following:
Constructs endpoint objects based on board insertion and IP registration.
Tears down endpoint objects based on board removal and IP unregistration.
Handles registration requests from H.323 endpoints that properly authenticate by using their extension number as a 'terminal alias', and the password as the registration encryption key.
Handles stimuli from all interfaces to establish and remove calls.
SLS remains in the Registered state as long as the socket to SLS is open.
