Patent ID: 7342877
Filing Date: 2008-03-11
Classification: H04L

Abstract:
1. A method for preventing loops in a ring topology of a computer network, the method comprising: receiving a first packet at an add/drop interface at a node on a shared packet ring; inserting a header containing an ID identifying the node at which the packet was received on the ring as an originating node; forwarding the packet onto the ring; receiving a second packet at the node and checking said ID and a bypass flag; if the node is not in a wrapping state, dropping said second packet if said ID identifies the node as the originating node and said bypass flag is not set, and forwarding said second packet on the ring if said ID does not identify the node as the originating node or said bypass flag is set; and if the node is in said wrapping state, forwarding said second packet on the ring only if a wrap flag in said second packet is not set.