System for digitized voice and data with means to compensate for variable path delays

Claim 1

In a communication system of the type in which voice signals for a sending station are formed into a packet and in which Packets from several sending stations are combined into a message and are transmitted to intended receiving stations, the system having alternate pathways through intermediate stations such that messages containing first or subsequent packets in a conversation may arrive at an intended receiving station at varying times in relation of the time when the voice signal originated, the intermediate stations having means for handling a message according to a priority carried by the message, and in which the receiving station has means for delaying the output of the first packet of a conversation to compensate for variations in the delays of said subsequent packets, the improvement comprising, means at the sending station for designating a message containing a first packet of a conversation to have a higher priority and for designating messages not containing a first packet of a conversation to have a lower priority, whereby the range of delays for the first packet of a conversation transmitted through said pathways is less than the range of delays for packets transmitted at a lower priority and thereby a reduction is made in the range of the minimum time interval between the latest arrival of said first packet of a conversation and the earliest arrival of a message containing the next packet of the same conversation, and means in a receiving station for delaying the first packet by an amount that is related to the more closely defined range of time intervals between said first packet and said next packet and is appropriate to a wide range of delays in the subsequent messages.