Implementation of Call Activity Detection for ATM Voice Services in Project Parakeet

Abstract : Asynchronous Transfer Mode (ATM) has been introduced into the land tactical communications system (specifically the Parakeet system) and offers the potential for increasing the effectiveness of the communications trunks by dynamically sharing the capacity between competing demands. Such a capability has been limited in respect of the trunks between the Parakeet circuit switches since Parakeet uses military standard protocols that do not integrate easily with the civil standard ATM. The Parakeet Adaptive Rate ATM Trunk (PARAT) was conceived to overcome this interface problem. The PARAT offers substantially improved data communications performance where lulls in voice usage can be exploited by data services sharing the ATM link. This report describes PARAT, in particular the mechanism to identify the moment-to-moment capacity requirements of the Parakeet inter-switch trunk and the method of carrying the variable bit rate stream over ATM.