Patent ID: 6680946
Filing Date: 2004-01-20
Classification: H04L

Abstract:
A method for transferring a series of layer-3 packets received from a non-ATM network through an ATM network composed of a plurality of ATM switches, comprising the steps of:at an ingress gateway interfacing between the non-ATM network and the ATM network, a) determining whether a flow of the series of packets has been registered; b) determining a transfer route from a first packet of the series of packets according to a layer-3 routing protocol when the flow has not been registered; c) transmitting a connection setup message to a next-hop ATM switch of the ATM network according to the transfer route to ensure a connection dedicated to transfer of the series of packets; and d) transferring the series of packets received from the non-ATM network to the next-hop ATM switch through the connection after the connection has been set up, e) monitoring the flow of the series of packets received through the connection at an egress gateway to (1) determine wheter to retain or release the connection; and (2) affecting retention and release of said connection, and wherein at each of nodes receiving the connection setup message from an upstream node which is one of the ingress gateway and an adjacent ATM switch; determining a transfer route from the connection setup message according to a layer-3 routing protocol; transmitting a connection setup message to a next-hop node of the ATM network according to the transfer route to ensure a connection dedicated to transfer of the series of packets to the next-hop node; and transferring the series of packets received from the upstream node to the next-hop node through the connection after the connection has been set up; and wherein, at said egress gateway which has received the connection setup message, affecting retention and release of said connection by: transmitting a connection retaining message to an upstream adjacent node using a default connection at intervals of a predetermined time period to retain the connection dedicated to transfer of the series of packets, when it is determined that the flow continues; and transmitting a connection releasing message to the upstream adjacent node using the default connection to release the connection dedicated to transfer of the series of packets, when it is determined that the flow is terminated.