Patents by Inventor Leah Li Zhang

Leah Li Zhang 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: 8908505
    Abstract: Example methods, apparatus and articles of manufacture to monitor communication paths in communication systems are disclosed. An example method includes identifying links of a communication system, the links communicatively coupling router pairs, identifying communication paths in the communication system, each of the communication paths being routed via one or more of the links, testing the links during a first interval by testing at least a first portion of the communication paths, testing the links during the second interval by testing at least a second portion of the communication paths, changing the first portion of the communication paths to include at least one of the communication paths from the second portion of the communication paths such that testing the first portion of the communication paths and testing the second portion of the communication paths collectively test each of the links, and identifying a link failure based on the testing.
    Type: Grant
    Filed: July 11, 2013
    Date of Patent: December 9, 2014
    Assignee: AT&T Intellectual Property I, L.P.
    Inventors: Zhijian Xu, Chee Ching, Kevin D'Souza, Joseph Lu, David H. Lu, Chen-Yui Yang, Leah Li Zhang
  • Patent number: 8630189
    Abstract: Example methods and apparatus to monitor tunnels within traffic engineering/fast reroute (TE/FRR) enabled networks are disclosed. A disclosed example apparatus includes a message interface to receive from a router a change alert notification for a traffic engineering (TE) tunnel, a router interrogator to interrogate the router to obtain updated path information for the TE tunnel in response to the received change alert notification, and a topology database interface to update a database representative of a tunnel topology of a TE/FRR enabled network based on the updated path information.
    Type: Grant
    Filed: September 17, 2009
    Date of Patent: January 14, 2014
    Assignee: AT&T Intellectual Property I, L.P.
    Inventors: Heng Wang, Shiow-Ching Ho, Leah Li Zhang
  • Publication number: 20130294258
    Abstract: Example methods, apparatus and articles of manufacture to monitor communication paths in communication systems are disclosed. An example method includes identifying links of a communication system, the links communicatively coupling router pairs, identifying communication paths in the communication system, each of the communication paths being routed via one or more of the links, testing the links during a first interval by testing at least a first portion of the communication paths, testing the links during the second interval by testing at least a second portion of the communication paths, changing the first portion of the communication paths to include at least one of the communication paths from the second portion of the communication paths such that testing the first portion of the communication paths and testing the second portion of the communication paths collectively test each of the links, and identifying a link failure based on the testing.
    Type: Application
    Filed: July 11, 2013
    Publication date: November 7, 2013
    Inventors: Zhijian Xu, Chee Ching, Kevin D'Souza, Joseph Lu, David H. Lu, Chen-Yui Yang, Leah Li Zhang
  • Patent number: 8498203
    Abstract: Example methods, apparatus and articles of manufacture to monitor communication paths in communication systems are disclosed. An example method includes identifying links of a communication system, the links communicatively coupling routers, identifying communication paths in the communication system, each of the communication paths being routed via one or more of the links, testing the links during a first interval by testing at least a first portion of the communication paths, testing the links during the second interval by testing at least a second portion of the communication paths, changing the first portion of the communication paths to include at least one of the communication paths from the second portion of the communication paths such that testing the first portion of the communication paths and testing the second portion of the communication paths collectively test each of the links, and identifying a link failure based on the testing.
    Type: Grant
    Filed: June 29, 2012
    Date of Patent: July 30, 2013
    Assignee: AT&T Intellectual Property I, L.P.
    Inventors: Zhijian Xu, Chee Ching, Kevin D'Souza, Joseph Lu, David H. Lu, Chen-Yui Yang, Leah Li Zhang
  • Publication number: 20120269073
    Abstract: Example methods, apparatus and articles of manufacture to monitor communication paths in communication systems are disclosed. An example method includes identifying links of a communication system, the links communicatively coupling routers, identifying communication paths in the communication system, each of the communication paths being routed via one or more of the links, testing the links during a first interval by testing at least a first portion of the communication paths, testing the links during the second interval by testing at least a second portion of the communication paths, changing the first portion of the communication paths to include at least one of the communication paths from the second portion of the communication paths such that testing the first portion of the communication paths and testing the second portion of the communication paths collectively test each of the links, and identifying a link failure based on the testing.
    Type: Application
    Filed: June 29, 2012
    Publication date: October 25, 2012
    Inventors: Zhijian Xu, Chee Ching, Kevin D'Souza, Joseph Lu, David H. Lu, Chen-Yui Yang, Leah Li Zhang
  • Patent number: 8279771
    Abstract: Example methods, apparatus and articles of manufacture to monitor communication paths in communication systems are disclosed. A disclosed example method includes identifying first and second inter-network communication links of a communication system, identifying a first plurality of router pairs associated with the first inter-network communication link, identifying a second plurality of router pairs associated with the second inter-network communication link, partitioning the first plurality of router pairs into a first subset of router pairs and a second subset of router pairs, partitioning the second plurality of router pairs into a third subset of router pairs and a fourth subset of router pairs, during a first time interval, performing first reachability tests for respective ones of the first and third subsets of router pairs, and during a second time interval, performing second reachability tests for respective ones of the second and fourth subsets of router pairs.
    Type: Grant
    Filed: September 25, 2009
    Date of Patent: October 2, 2012
    Assignee: AT&T Intellectual Property I, L.P.
    Inventors: Zhijian Xu, Chee Ching, Kevin D'Souza, Joseph Lu, David H. Lu, Chen-Yui Yang, Leah Li Zhang
  • Publication number: 20110075567
    Abstract: Example methods, apparatus and articles of manufacture to monitor communication paths in communication systems are disclosed. A disclosed example method includes identifying first and second inter-network communication links of a communication system, identifying a first plurality of router pairs associated with the first inter-network communication link, identifying a second plurality of router pairs associated with the second inter-network communication link, partitioning the first plurality of router pairs into a first subset of router pairs and a second subset of router pairs, partitioning the second plurality of router pairs into a third subset of router pairs and a fourth subset of router pairs, during a first time interval, performing first reachability tests for respective ones of the first and third subsets of router pairs, and during a second time interval, performing second reachability tests for respective ones of the second and fourth subsets of router pairs.
    Type: Application
    Filed: September 25, 2009
    Publication date: March 31, 2011
    Inventors: Zhijian Xu, Chee Ching, Kevin D'Souza, Joseph Lu, David H. Lu, Chen-Yui Yang, Leah Li Zhang
  • Publication number: 20110063985
    Abstract: Example methods and apparatus to monitor tunnels within traffic engineering/fast reroute (TE/FRR) enabled networks are disclosed. A disclosed example apparatus includes a message interface to receive from a router a change alert notification for a traffic engineering (TE) tunnel, a router interrogator to interrogate the router to obtain updated path information for the TE tunnel in response to the received change alert notification, and a topology database interface to update a database representative of a tunnel topology of a TE/FRR enabled network based on the updated path information.
    Type: Application
    Filed: September 17, 2009
    Publication date: March 17, 2011
    Inventors: Heng Wang, Shiow-Ching Ho, Leah Li Zhang