Patents Assigned to 3Com Corportion
  • Patent number: 6912589
    Abstract: A method and system for efficiently handling forwarding of multicast packets by ignoring VLAN (virtual local area network) context during lookup. In one embodiment, the present invention receives, at an intermediate device, multicast registration information for a client. The present embodiment then creates a forwarding database of the multicast registration information. In the present embodiment, when handling a multicast packet at an intermediate device, the present invention accesses the multicast registration information stored in the forwarding database. More particularly, in this embodiment, the present invention accesses the multicast registration information stored in the forwarding database without utilizing VLAN context of the client. As a result, the present invention allows the intermediate device to forward a single multicast packet which will later be supplied to registered member ports. The member ports apply the appropriate VLAN context.
    Type: Grant
    Filed: March 30, 1999
    Date of Patent: June 28, 2005
    Assignee: 3Com Corportion
    Inventors: Vipin Kumar Jain, Peter Si-Sheng Wang
  • Patent number: 6611502
    Abstract: Modifications to the spanning tree algorithm allow bad news to propagate quickly by providing that protocol entities on bridges process inferior information sent by the designated bridge for each LAN. In addition, bridges use per port hello timers to stimulate information propagation, setting it to suit local link characteristics. No changes to the format of bridge protocol data units (BPDUs) as specified in the IEEE Standard 802.1D are required, and the algorithm for computing the topology of the network remains unchanged. Techniques have been adopted for expiring information and recomputing the spanning tree upon detection of link failure, upon receipt of a message having a message age greater than its accompanying maximum age, or if the port hello time algorithm detects a loss of link. Rules for propagating information are provided allowing rapid propagation of changes. Finally, techniques for burning out information in a configuration message are adopted.
    Type: Grant
    Filed: January 15, 1999
    Date of Patent: August 26, 2003
    Assignee: 3Com Corportion
    Inventor: Michael John Seaman