Patents by Inventor George Varghese

George Varghese has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5151899
    Abstract: A packet data communication network employs sequence numbers in message packets to identify the packets transmitted for a message, so that the order of packets can be checked, and so that the occurrence of lost or duplicated packets can be detected. A method of keeping track of these sequence numbers is provided. Any number below or above a bounded sequence number acceptance window is ignored (not accepted). Bit maps are established for the range of numbers within the bounded window, each bit representing a sequence number and the bit maps indexed by sequence number. One bit map is a received packet map, used to keep track of which sequence numbers have been received and thus to filter duplicate sequence numbers. An end-of-message bit map is used to record the positions of packets having end-of-message flags, and this is used with the received packet map to determine whether all packets of a message have been received, so that an end-of-message trigger can be generated.
    Type: Grant
    Filed: February 11, 1991
    Date of Patent: September 29, 1992
    Assignee: Digital Equipment Corporation
    Inventors: Robert E. Thomas, George Varghese, Robert J. Souza, George A. Harvey
  • Patent number: 5086428
    Abstract: A method and apparatus for creating and managing databases in routers of a routing network. The databases store link state packets, each packet being originated by nodes in the network, and transmitted to other nodes through the network. Each packet contains data identifying its originating node, a sequence number in a linear space indicating its place in the sequence of packets generated by its originating node, and an age value indicating the time remaining before it expires. The contents of the databases are updated by newly received packets. In addition, the nodes themselves are reset if the packets currently in the network have later sequence numbers than new packets. Also, a mechanism is provided to purge the databases of packets from a given router by issuing a purging packet.
    Type: Grant
    Filed: June 9, 1989
    Date of Patent: February 4, 1992
    Assignee: Digital Equipment Corporation
    Inventors: Radia J. Perlman, George Varghese, Anthony G. Lauck
  • Patent number: 5018137
    Abstract: A method for improving communications in a bridge network between end nodes involving sensing trunking configurations and executing binding schemes to make certain daughter bridges involved in the trunking conditions behave as a plurality of bridges and forward messages in the correct time sequence. This can be done by creating "forwarding groups" associating different groups of networks connected to those daughter bridges.
    Type: Grant
    Filed: October 16, 1990
    Date of Patent: May 21, 1991
    Assignee: Digital Equipment Corporation
    Inventors: Floyd J. Backes, George Varghese, Charles W. Kaufman