Patents by Inventor Robert H. Thomas

Robert H. Thomas 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: 7969898
    Abstract: A technique for breaking a loop caused by looping alternate paths associated with a prefix in a communications network. One or more non-looping alternate paths associated with the prefix that exclude a first node in the communications network are identified. One or more alternate paths from nodes in the loop that are associated with the prefix are identified. An identified path that intersects with an identified non-looping path is established as an alternate path associated with the prefix at a node in the loop.
    Type: Grant
    Filed: March 9, 2007
    Date of Patent: June 28, 2011
    Assignee: Cisco Technology, Inc.
    Inventors: Alex Raj, Robert H. Thomas, Anna Charny, Prabhu Vaithilingam
  • Patent number: 7945696
    Abstract: In one embodiment, one or more tunnel mesh groups may be established in at least a portion of a computer network, where each tunnel mesh group corresponds to a differentiated routing profile. Traffic may then be received at the portion of the computer network, the traffic indicating a particular differentiated routing profile (e.g., based on a received label corresponding to the differentiated routing profile as advertised by the portion of the computer network). Accordingly, the traffic may be routed through the portion of the computer network along a tunnel of a particular tunnel mesh group corresponding to the particular differentiated routing profile traffic.
    Type: Grant
    Filed: November 30, 2007
    Date of Patent: May 17, 2011
    Assignee: Cisco Technology, Inc.
    Inventors: Jean-Philippe Vasseur, Jeff Apcar, Jim Guichard, Robert H. Thomas
  • Patent number: 7936668
    Abstract: A given router in the core of a label-switching network identifies a group of routers to receive common label binding information for later routing packets along respective paths through the label-switching network. One way to identify which of multiple routers to include as a member of the group to receive the same label information is to analyze egress policies associated with downstream routers in the label-switching network. Based on this analysis, the given router identifies group members as routers having a substantially same egress policy as each other. The given router then allocates memory resources to store a common set of label information to be distributed to each member in the group of routers having the same egress policy. After populating the memory resources with label information, the given router distributes a common set of label information to each router in the group of routers.
    Type: Grant
    Filed: May 26, 2005
    Date of Patent: May 3, 2011
    Assignee: Cisco Technology, Inc.
    Inventors: James N. Guichard, Matthew H. Birkner, Robert H. Thomas, Roy M. Brooks
  • Patent number: 7899049
    Abstract: A method, apparatus and computer program product for minimizing or preventing duplicate traffic during point to multipoint tree switching in a network. In its operation, embodiments disclosed herein utilize control plane trigger mechanisms to handle the receipt of duplicate traffic by network entities after the occurrence of a network failure event. Generally, the control plane trigger mechanism prevents a network entity from processing multicast traffic from both old and new upstream data paths resulting from typical network convergence procedures. The methods and apparatus describe herein apply to standard rerouting procedures as well as fast rerouting procedures for multicast traffic in a network.
    Type: Grant
    Filed: August 1, 2006
    Date of Patent: March 1, 2011
    Assignee: Cisco Technology, Inc.
    Inventors: Alex E. Raj, Robert H. Thomas
  • Patent number: 7684350
    Abstract: A method of distributing labels in a label distribution protocol multicast network having a root node and at least one leaf node comprises the steps, performed at a receiving node, of receiving a label and path vector from a distributing node, carrying out loop or convergence detection from the received path vector and, if convergence or no loop is detected, sending a receiving node label and path vector to its nexthop node in the network.
    Type: Grant
    Filed: March 16, 2006
    Date of Patent: March 23, 2010
    Assignee: Cisco Technology, Inc.
    Inventors: Alex E. Raj, Eric C. Rosen, Robert H. Thomas, IJsbrand Wijnands
  • Patent number: 7609620
    Abstract: A method and apparatus method for providing fast rerouting in a network is presented. The method and apparatus assign a first local label for a prefix, and assign a second local label for the prefix. The first local label is advertised to an upstream peer and the second local label is advertised to a downstream peer. A forwarding entry from the first local label for a prefix is switched to the second local label for the prefix when a failure of a link or next hop is detected.
    Type: Grant
    Filed: August 15, 2005
    Date of Patent: October 27, 2009
    Assignee: Cisco Technology, Inc.
    Inventors: Alex E. Raj, Robert H. Thomas, Prabhu Vaithilingam
  • Publication number: 20090144443
    Abstract: In one embodiment, one or more tunnel mesh groups may be established in at least a portion of a computer network, where each tunnel mesh group corresponds to a differentiated routing profile. Traffic may then be received at the portion of the computer network, the traffic indicating a particular differentiated routing profile (e.g., based on a received label corresponding to the differentiated routing profile as advertised by the portion of the computer network). Accordingly, the traffic may be routed through the portion of the computer network along a tunnel of a particular tunnel mesh group corresponding to the particular differentiated routing profile traffic.
    Type: Application
    Filed: November 30, 2007
    Publication date: June 4, 2009
    Inventors: Jean-Philippe Vasseur, Jeff Apcar, Jim Guichard, Robert H. Thomas
  • Publication number: 20080031130
    Abstract: A method, apparatus and computer program product for minimizing or preventing duplicate traffic during point to multipoint tree switching in a network. In its operation, embodiments disclosed herein utilize control plane trigger mechanisms to handle the receipt of duplicate traffic by network entities after the occurrence of a network failure event. Generally, the control plane trigger mechanism prevents a network entity from processing multicast traffic from both old and new upstream data paths resulting from typical network convergence procedures. The methods and apparatus describe herein apply to standard rerouting procedures as well as fast rerouting procedures for multicast traffic in a network.
    Type: Application
    Filed: August 1, 2006
    Publication date: February 7, 2008
    Inventors: Alex E. Raj, Robert H. Thomas
  • Patent number: 7286529
    Abstract: A tag-switching router on a tag-switching network establishing a single tag distribution protocol (TDP) session with a peer for the advertisement of tag bindings shared by two or more interfaces and contemporaneously establishing with the peer one or more additional TDP sessions for the advertisement of tag bindings dedicated for use by specific interfaces. Each router interface has an assigned tag space comprised incoming tags that are appended by the peer to input data packets forwarded by the peer. A new Hello message carried in a TDP protocol data unit (PDU) is introduced for use in a TDP discovery mechanism. The router periodically multicasts a specific Hello message from each tag-switching enabled interface and a router TDP identifier in the TDP PDU header identifies the tag space that the router has assigned to the interface.
    Type: Grant
    Filed: January 24, 2003
    Date of Patent: October 23, 2007
    Assignee: Cisco Technology, Inc.
    Inventor: Robert H. Thomas
  • Patent number: 6512768
    Abstract: A tag-switching router on a tag-switching network establishing a single tag distribution protocol (TDP) session with a peer for the advertisement of tag bindings shared by two or more interfaces and contemporaneously establishing with the peer one or more additional TDP sessions for the advertisement of tag bindings dedicated for use by specific interfaces. Each router interface has an assigned tag space comprised incoming tags that are appended by the peer to input data packets forwarded by the peer. A new Hello message carried in a TDP protocol data unit (PDU) is introduced for use in a TDP discovery mechanism. The router periodically multicasts a specific Hello message from each tag-switching enabled interface and a router TDP identifier in the TDP PDU header identifies the tag space that the router has assigned to the interface.
    Type: Grant
    Filed: February 26, 1999
    Date of Patent: January 28, 2003
    Assignee: Cisco Technology, Inc.
    Inventor: Robert H. Thomas
  • Patent number: 4868932
    Abstract: A supplementary self-contained cleaning fluid distribution system provides for the selective flushing and cleaning of the waste fluid holding tanks of a recreational vehicle. From an external connection cleaning fluid is directed to grey water or sewage tanks respectively, by means of a tank selector and backflow prevention system. Components of the system include a pair of normally closed solenoid valves and a normally open pressure switch responsive to the delivered pressure of the cleaning fluid. A predetermined reduction of the cleaning fluid supply pressure automatically isolates the vehicle system from the external fluid supply.
    Type: Grant
    Filed: September 2, 1988
    Date of Patent: September 26, 1989
    Assignee: Swan Industries, Inc.
    Inventors: Robert H. Thoma, J. David Swan
  • Patent number: 4605587
    Abstract: Improved retention on yarn and processing properties have been discovered in a composition of matter comprising meta and para pyromellitates ##STR1## and 2 to 50 percent by weight of specific dimers of I. and II., wherein A is (CH.sub.2).sub.2 (CF.sub.2).sub.n CF.sub.3, where n is 5 to 13 and B is CH.sub.2 CHOHCH.sub.2 Cl.
    Type: Grant
    Filed: February 19, 1982
    Date of Patent: August 12, 1986
    Assignee: Allied Corporation
    Inventors: Robert H. Thomas, Willis B. Hammond, Michael P. Friedberger, William A. Archie
  • Patent number: 4604316
    Abstract: Improved retention on yarn and processing properties have been discovered in a composition of matter comprising meta and para pyromellitates ##STR1## and 70 to 95 percent by weight of specific dimers and other oligomers of I. and II., wherein A is (CH.sub.2).sub.2 (CF.sub.2).sub.n CF.sub.3, where n is 5 to 13 and B is CH.sub.2 CHOHCH.sub.2 Cl.
    Type: Grant
    Filed: September 14, 1982
    Date of Patent: August 5, 1986
    Assignee: Allied Corporation
    Inventors: Robert H. Thomas, deceased, by Mary A. Thomas, executrix, Willis B. Hammond, Michael P. Friedberger, William A. Archie