FR5099 - ISDN SUSPEND / ISDN RESUME Message Support

Important! This feature is implemented for Euro ISDN only and for ISDN Series 3 cards.

Purpose

On an ISDN network, the user sends an SUSPEND message to request the network to suspend a call. The response to this message can be a SUSPEND ACKNOWLEDGE sent by the network to the user to indicate completion of a request to suspend the call.

The network can also respond to the user with a SUSPEND REJECT indicating failure to suspend the call. When the user receives the SUSPEND ACK message it releases the B-channel and call reference and enters the NULL state (0).

If the user receives a SUSPEND REJECT response it returns to the ACTIVE state. If no response is received by the user it notifies the user application and returns to the ACTIVE state.

To re-establish the call, the user sends a RESUME message to the network. The network will validate the message and respond with a RESUME ACKNOWLEDGE or RESUME REJECT. When the user receives the RESUME ACK message it enters the ACTIVE state. If the user receives a RESUME REJECT response it remains in the NULL state. If no response is received by the user it clears the call with cause 102 (timer expiry).