Patent ID: 8374323

Claim:
A method for notifying a caller that a call destination who was initially unavailable is now available, comprising the steps: a. detecting that the caller's attempt to set-up a call with the call destination has failed using an availability notification system (ANS) connected to a network associated with at least one of the caller and destination, the ANS having a detection task module executing a detection task on a processor thereof and operative to: 1. receive the number identifications of the caller and the destination; 2. receive a release message associated with the call attempt, said call release message originating in an MSC of the destination's network, the release message including one or more cause-indicators; 3. test the cause-indicator in the received release message in a machine executing the ANS to determine a match to a prescribed criterion that is indicative of an incomplete call attempt that can be later connected; and b. in the event of the match, executing a notification task within the ANS to at least one of caller and destination using a notification task module; wherein the notification task operates so as to periodically assess the availability of the destination by sending a message to the destination and receiving an acknowledgement thereof for a predefined time limit, wherein the message is stopped short of reaching a terminal of the destination until the destination becomes available; wherein, if the destination is assessed to have become available within the predefined time limit, the notification task performs the additional step at the ANS of sending at least one of the caller and the destination a notification that a call can be established.