Apparatus and method for interconnecting isochronous systems over packet-switched networks

Abstract

A telecommunications system ( ) is provided that includes a first controller ( ) and a second controller ( ) coupled using a packet-switched network ( ). The controllers provide a low cost means of coupling isochronous telecommunication devices. The first controller ( ) receives one or more isochronous input channels from a common control shelf ( ), such as a private branch exchange (PBX), over a circuit-switched network ( ). The first controller ( ) encapsulates an isochronous frames from the common control shelf ( ) into a data frame that is transferrable over the packet-switched network ( ). The second controller ( ) is configured to receive the data frame and extract the isochronous frame, which is then transmitted to a peripheral shelf ( ), such as a line trunk unit (LTU), using an isochronous circuit-switched network ( ). The controllers contain identical functionality, permitting bi-directional transmission of data between the common control and peripheral shelves. Each controller includes multiplex/de-multiplex functions normally associated with isochronous telephony, as well as a packetize/de-packetize functions for transferring data over the packet-switched network ( ). The arrival rate of the data packets is used for synchronizing the two controllers.