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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).

See Integrated Services Digital Network.
Positive acknowledgment to a message