Patents by Inventor David S. Walker

David S. Walker 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: 7050435
    Abstract: An integrated circuit monitors the most active traffic flow rates on a communications network by using a leaky bucket model having a variable fill rate. As a switch receives packets, the packet identifications are sampled. A sampled packet identification is compared to record identifications in a table of identifications. If the sampled and record identifications match, an activity value for the packet identification is increased by an amount inversely proportional to an activity value associated with the record identification. If the sampled and record identifications do not match, the activity value is decreased. Record identifications are removed from the table when the activity value decreases to a specified level. New sampled identifications are added to the table if empty records exist.
    Type: Grant
    Filed: March 4, 2003
    Date of Patent: May 23, 2006
    Assignee: Cisco Technology, Inc.
    Inventors: David S. Walker, Daniel R. Ullum
  • Patent number: 6886118
    Abstract: The method can be implemented on a processor executing software instructions stored in memory. In one embodiment of the invention, the method includes receiving an Ethernet frame, wherein the Ethernet frame comprises an IP datagram, wherein the IP datagram comprises an IP header and an IP payload, wherein the IP payload comprises a User Datagram Protocol (UDP) header. When the Ethernet frame is received, a length in bytes of the IP payload of the IP datagram is calculated.
    Type: Grant
    Filed: April 4, 2003
    Date of Patent: April 26, 2005
    Assignee: Cisco Technology, Inc.
    Inventors: Kenneth M. Rose, Venkateshwar R. Pullela, David S. Walker, Kevin C. Wong, Kaichuan He, Yu Kwong Ng
  • Publication number: 20040205228
    Abstract: Disclosed is a method and apparatus for checking link layer protocol frames such as Ethernet frames. The method can be implemented on a processor executing software instructions stored in memory. In one embodiment of the invention, the method includes receiving an Ethernet frame, and counting data bytes of the Ethernet frame to generate a total number of counted bytes. The total number of counted bytes can be used to calculate a data length of a datagram of the Ethernet frame. Once calculated, the datagram data length can be compared to a predetermined value. If the datagram length does not fall within an acceptable range of the predetermined value, the Ethernet frame may be dropped so that the Ethernet frame does not reach its final destination.
    Type: Application
    Filed: March 6, 2003
    Publication date: October 14, 2004
    Inventors: Kenneth M. Rose, Venkateshwar R. Pullela, David S. Walker, Kevin C. Wong, Kaichuan He, Yu Kwong Ng
  • Publication number: 20040177106
    Abstract: The method can be implemented on a processor executing software instructions stored in memory. In one embodiment of the invention, the method includes receiving an Ethernet frame, wherein the Ethernet frame comprises an IP datagram, wherein the IP datagram comprises an IP header and an IP payload, wherein the IP payload comprises a User Datagram Protocol (UDP) header. When the Ethernet frame is received, a length in bytes of the IP payload of the IP datagram is calculated.
    Type: Application
    Filed: April 4, 2003
    Publication date: September 9, 2004
    Inventors: Kenneth M. Rose, Venkateshwar R. Pullela, David S. Walker, Kevin C. Wong, Kaichuan He, Yu Kwong Ng
  • Publication number: 20040177275
    Abstract: The method can be implemented on a processor executing software instructions stored in memory. In one embodiment of the invention, the method includes receiving an Ethernet frame, wherein the Ethernet frame comprises a Transmission Control Protocol (TCP) header, wherein the TCP header comprises a TCP header length value. When the Ethernet frame is received, the TCP header length value is compared to a predetermined value.
    Type: Application
    Filed: April 4, 2003
    Publication date: September 9, 2004
    Inventors: Kenneth M. Rose, Venkateshwar R. Pullela, David S. Walker, Kevin C. Wong, Kaichuan He, Yu Kwong Ng
  • Patent number: 6567379
    Abstract: An integrated circuit monitors the most active traffic flow rates on a communications network by using a leaky bucket model having a variable fill rate. As a switch receives packets, the packet identifications are sampled. A sampled packet identification is compared to record identifications in a table of identifications. If the sampled and record identifications match, an activity value for the packet identification is increased by an amount inversely proportional to an activity value associated with the record identification. If the sampled and record identifications do not match, the activity value is decreased. Record identifications are removed from the table when the activity value decreases to a specified level. New sampled identifications are added to the table if empty records exist.
    Type: Grant
    Filed: June 9, 1999
    Date of Patent: May 20, 2003
    Assignee: Cisco Technology, Inc.
    Inventors: David S. Walker, Daniel R. Ullum