Tele

Ft defines a call handling protocol similar to the one that has evolved with voice telephony since the late 19th Century. It is based on a canonical flow of these states with manifold exceptions:

1.   DOWN/OFFHOOK/REJECT 

   All subscribers are initially are in this state and may move to it by personal or network events.

2.    AFK/BUSY

   A subscriber controlled state which blocks calls until the subscriber sets READY.

3.   ACCEPT/ANSWER/READY 

   A subscriber moves to this state after connecting assuming no event, such as their or the network having set a different state.

4.   BUFF/WAIT 

   A network controlled state which indicates incoming events for the subscriber.

5.   CALL/PAGE  

   A state in which the subscriber can or has initiated a call.