Patent ID: 6615273
Filing Date: 2003-09-02
Classification: H04L

Abstract:
A method for propagating a target identifier address resolution packet (TARP PDU) over a large network that includes a plurality of nodes each having an IS-IS routing engine with a forwarding database which is dynamically updated to determine optimal routes between network nodes, said method comprising the steps of:broadcasting, by an originating node, the TARP PDU that is addressed to a target node; receiving, by a plurality of receiving nodes, the TARP PDU; storing, by the plurality of receiving nodes, the TARP PDU and an interface identifier (1nr1) which identifies an interface over which the receiving node received the TARP PDU from the originating node; determining, by each receiving node, whether the receiving node is in a same routing area as the originating node; retrieving, from a forwarding database of the IS-IS routing engine, an optimal interface identifier (1ns1), wherein the 1ns1 identifies a reverse shortest path interface which the receiving node would use for transmission back to the originating node; comparing, by the receiving node, the 1ns1 and the 1nr1; broadcasting, if the receiving node determines that the 1ns1 is equal to the 1nr1, the TARP PDU onto the network; and dropping, if the receiving node determines that the 1ns1 is not equal to the 1nr1, the TARP PDU, thereby reducing the creation of loops on the network.