Patents by Inventor Kadangode K. Ramakrishnan

Kadangode K. Ramakrishnan 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: 8532137
    Abstract: A method and architecture for Packet-Aware Transport Networks (PATN) which supports both packet and traditional TDM services and which leverages an assemblage of emerging technologies to provide efficient aggregation and switching of packet traffic in metro networks. The PATN provides significant cost savings to carriers by reducing the number of network elements, reducing transport costs through statistical multiplexing, and eliminating the need for redundant multiplexing operations.
    Type: Grant
    Filed: March 26, 2004
    Date of Patent: September 10, 2013
    Assignee: AT&T Intellectual Property II, L.P.
    Inventors: Thomas Scott Afferton, Luis Aguirre-Torres, Robert Duncan Doverspike, Charles Robert Kalmanek, Jr., Kadangode K. Ramakrishnan
  • Patent number: 8510562
    Abstract: A method for transferring content includes requesting the content from a serving peer and sending the content to a requesting peer. Requesting the content includes sending a request to a tracker, receiving a request token, a path identifier, and a first peer identifier from the tracker, and sending a request message to a second peer. The first peer identifier includes an identity of a first peer, and the request message includes the request token, the path identifier, and the first peer identifier. Sending the content includes receiving the request token and the path identifier from a third peer, sending a return message to a fourth peer, and transferring the content from the serving peer to the requesting peer through a transfer path. The return message includes the path identifier and a second peer identifier. The second peer identifier includes an identity of a fifth peer. The transfer path includes at least the second, fourth, and fifth peers.
    Type: Grant
    Filed: March 22, 2010
    Date of Patent: August 13, 2013
    Assignee: AT&T Intellectual Property I, L.P.
    Inventors: Kadangode K. Ramakrishnan, Vijay Gopalakrishnan, Fang Yu, David Lee
  • Patent number: 8473557
    Abstract: Methods and apparatus to migrate virtual machines between distributive computing networks across a wide area network are disclosed. A disclosed example method includes establishing a data link across a wide area network between a first distributive computing network and a second distributive computing network, the first distributive computing network including a virtual machine operated by a first host communicatively coupled to a virtual private network via a first virtual local area network, communicatively coupling a second host included within the second distributive computing network to the virtual private network via a second virtual local area network, and migrating the virtual machine via the data link by transmitting a memory state of at least one application on the first host to the second host while the at least one application is operating.
    Type: Grant
    Filed: August 24, 2010
    Date of Patent: June 25, 2013
    Assignee: AT&T Intellectual Property I, L.P.
    Inventors: Kadangode K. Ramakrishnan, Jacobus Van Der Merwe, Prashant Shenoy, Timothy Wood
  • Publication number: 20130104175
    Abstract: A method includes receiving demand information for a first segment of a media content item and receiving demand information for a second segment of the media content item. The method includes assigning the first segment to a first set of distribution nodes of a media content distribution system based at least partially on the demand information for the first segment and based at least partially on a first cost function and assigning the second segment to a second set of distribution nodes of the media content distribution system based at least partially on the demand information for the second segment and based at least partially on a second cost function. The media content distribution system includes a plurality of distribution nodes and each distribution node is configured to provide media content items to at least some of a plurality of endpoints.
    Type: Application
    Filed: October 25, 2011
    Publication date: April 25, 2013
    Applicant: AT&T Intellectual Property I.L.P.
    Inventors: David Applegate, Aaron Archer, Kyung-Wook Hwang, Vijay Gopalakrishnan, Seungjoon Lee, Kadangode K. Ramakrishnan, Deborah F. Swayne
  • Patent number: 8396011
    Abstract: A method of configuring a network access device connected to an access network connected to a plurality of service networks, the network device having a first network address allocated to a subscriber of services of a first service provider provided by a first service network, with a new network address allocated to a second subscriber of services of either the first service provider, or a second service provider provided by a second service network. The method comprises the steps of: sending a request from the network access device to the access network with user credentials for the second subscriber requesting access to the first service provider or a change to the second service provider; receiving a response from the access network; and initiating a network address change request using a configuration protocol.
    Type: Grant
    Filed: August 16, 2010
    Date of Patent: March 12, 2013
    Assignee: AT&T Intellectual Property II, L.P.
    Inventors: Sean E. Carolan, John W. Garrett, Charles Robert Kalmanek, Jr., Han Q. Nguyen, Kadangode K. Ramakrishnan
  • Publication number: 20130051377
    Abstract: Methods and apparatus to utilize network coding in a wireless network are disclosed.
    Type: Application
    Filed: August 26, 2011
    Publication date: February 28, 2013
    Inventors: Hulya Seferoglu, Athina Markopoulou, Kadangode K. Ramakrishnan
  • Patent number: 8331369
    Abstract: Example methods and apparatus to distribute network IP traffic are disclosed. A disclosed example method includes receiving a first IP control packet at an input of a first server, the first IP control packet being received from a first router, selecting a second router within a router array associated with the first router to send the first IP control packet, the first server selecting the second router by matching a destination IP address of the first IP control packet to a first IP address subspace associated with the second router, transmitting the first IP control packet to the second router, and updating a forwarding table in the first router by associating the destination IP address of the first IP control packet with a first control path from the first router to the second router.
    Type: Grant
    Filed: December 24, 2008
    Date of Patent: December 11, 2012
    Assignee: AT&T Intellectual Property I, L.P.
    Inventors: Cheng Tien Ee, Lee M. Breslau, Kadangode K. Ramakrishnan
  • Patent number: 8305888
    Abstract: Providing transport protocol within a communication network having a lossy link. The receiver distinguishes between packets received with non-congestion bit errors and packets having been not at all received due to congestion. When packets are received with non-congestion bit errors, the receiver sends selective acknowledgments indicating that the packets were received with bit errors while suppressing duplicate acknowledgments to prevent the invocation of a congestion mechanism.
    Type: Grant
    Filed: November 24, 2009
    Date of Patent: November 6, 2012
    Assignee: AT&T Intellectual Property II, L.P.
    Inventor: Kadangode K. Ramakrishnan
  • Publication number: 20120269058
    Abstract: A second link in a network is reconfigured after failure of a first link, so that multiple-link failures may be survived. After receipt of an OSPF link state advertisement (LSA) indicating use of a backup path bl after the failure of link l, new backup paths are determined for each impacted link (x,y) that has a backup path sharing one or more links with the backup path bl. The new backup paths are computed while ignoring the failed link l, the impacted link (x,y), and links common to the backup paths b(x,y) and bl. The LSA protocol is modified to accommodate information used in determining whether a link is an impacted link.
    Type: Application
    Filed: June 29, 2012
    Publication date: October 25, 2012
    Inventors: Kadangode K. Ramakrishnan, Rakesh Kumar Sinha, Ajay Kumar Todimala
  • Patent number: 8295203
    Abstract: Methods and systems are described to store state used to forward multicast traffic. The system includes a receiving module to receive request to add a first node to a membership tree. The membership tree includes a first plurality of nodes associated with a multicast group. The system further includes a processing module to identify a second node in the first plurality of nodes and to communicate a node identifier that identifies the first node over a network to the second node. The node identifier is to be stored at the second node to add the first node to the membership tree. The node identifier is further to be stored in the membership tree exclusively at the second node to enable the second node to forward the multicast traffic to the first node.
    Type: Grant
    Filed: April 1, 2008
    Date of Patent: October 23, 2012
    Assignee: AT&T Intellectual Property I, L.P.
    Inventors: Kadangode K. Ramakrishnan, Divesh Srivastava, Tae W. Cho, Yin Zhang, Michael Rabinovich
  • Patent number: 8284911
    Abstract: A call is forwarded by connecting the call between an originating location and a forwarding location without connecting the call through a terminating location. The originating location is associated with a calling party. The terminating location is associated with a dialed number. The terminating location and the forwarding location is associated with the called party. A bill for the call is apportioned between the calling party and the called party. The bill portion for the calling party is a function of the originating location and the terminating location. The bill portion for the called party is a function of the terminating location and the forwarding location.
    Type: Grant
    Filed: December 7, 2009
    Date of Patent: October 9, 2012
    Assignee: AT&T Intellectual Property II, L.P.
    Inventors: Charles Robert Kalmanek, Jr., William Todd Marshall, Partho Pratim Mishra, Douglas M Nortz, Kadangode K. Ramakrishnan
  • Publication number: 20120252473
    Abstract: Network resources for a call between a calling party and a called party are allocated. The network resources for the call are reserved based on a reservation request. The network resources are reserved before any one network resource from the reserved network resources is committed. The reserved network resources for the call are committed when a called party indicates acceptance for the call.
    Type: Application
    Filed: June 12, 2012
    Publication date: October 4, 2012
    Inventors: Charles Robert Kalmanek, JR., William Todd Marshall, Partho Pratim Mishra, Douglas M. Nortz, Kadangode K. Ramakrishnan
  • Patent number: 8249059
    Abstract: Network resources for a call between a calling party and a called party are allocated. The network resources for the call are reserved based on a reservation request. The network resources are reserved before any one network resource from the reserved network resources is committed. The reserved network resources for the call are committed when a called party indicates acceptance for the call.
    Type: Grant
    Filed: August 13, 2010
    Date of Patent: August 21, 2012
    Assignee: AT&T Intellectual Property II, L.P.
    Inventors: Charles Robert Kalmanek, Jr., William Todd Marshall, Partho Pratim Mishra, Douglas M Nortz, Kadangode K. Ramakrishnan
  • Patent number: 8243586
    Abstract: A second link in a network is reconfigured after failure of a first link, so that multiple-link failures may be survived. After receipt of an OSPF link state advertisement (LSA) indicating use of a backup path bl after the failure of link l, new backup paths are determined for each impacted link (x,y) that has a backup path sharing one or more links with the backup path bl. The new backup paths are computed while ignoring the failed link l, the impacted link (x,y), and links common to the backup paths b(x,y) and bl. The LSA protocol is modified to accommodate information used in determining whether a link is an impacted link.
    Type: Grant
    Filed: November 24, 2009
    Date of Patent: August 14, 2012
    Assignee: AT&T Intellectual Property I, L.P.
    Inventors: Kadangode K. Ramakrishnan, Rakesh Kumar Sinha, Ajay Kumar Todimala
  • Publication number: 20120158983
    Abstract: A content monitor includes a processor that at least receives requests from a plurality of clients for content, instructs each client to retry their respective request at a first later time if the request is received before a first time, counts the requests to determine if a number of the requests exceeds a threshold if the request is received before a second time, instructs each client to retry their respective request at a second later time if the counted number of requests does not exceed a first threshold, instructs each client to join a multicast group to receive the content when the number of requests exceeds the first threshold, and counts a number of late clients joining the multicast group after a first portion of the content has been sent to the multicast group.
    Type: Application
    Filed: February 24, 2012
    Publication date: June 21, 2012
    Applicant: AT&T Intellectual Property I, L.P.
    Inventors: Alan L. Glasser, Andrew G. Gauld, Vijay Gopalakrishnan, John F. Lucas, Kadangode K. Ramakrishnan
  • Publication number: 20120120801
    Abstract: Example methods, apparatus and articles of manufacture to route policy requests are disclosed. A disclosed example method includes sending bandwidth probe packets at a probing rate, receiving a packet containing an indication representative of whether the probe packets triggered congestion, and selecting a transmission rate for sending data packets based on the probing rate and the indication.
    Type: Application
    Filed: November 17, 2010
    Publication date: May 17, 2012
    Inventors: Kadangode K. Ramakrishnan, Mayutan Arumaithurai, Xiaoming Fu
  • Publication number: 20120096081
    Abstract: A method includes receiving at a directory server a notification from a client system, where the notification indicates that the first client received a corrupt packet of a playfile from a first peer. The method also includes determining if the first peer is a poor quality peer, updating a first peer score for the first peer if the first peer is not a poor quality peer, identifying a second peer that is not on a blacklist, and providing a peer identification associated with the second peer to the client system.
    Type: Application
    Filed: December 21, 2011
    Publication date: April 19, 2012
    Applicant: AT&T INTELLECTUAL PROPERTY I, L.P.
    Inventors: Kadangode K. Ramakrishnan, Vijay Gopalakrishnan, Fang Yu
  • Patent number: 8150993
    Abstract: A content delivery system includes a unicast content delivery module, a multicast content delivery module, and a content monitor module. The unicast content delivery module is configured to provide content using a unicast protocol, and the multicast content delivery module is configured to provide the content using a multicast protocol. The content monitor module is configured to receive requests from a plurality of clients for the content, count the requests to determine if the number of requests exceeds a threshold, and instruct the plurality of clients to receive the content from the multicast content delivery module when the number of requests exceeds the threshold.
    Type: Grant
    Filed: October 29, 2009
    Date of Patent: April 3, 2012
    Assignee: AT&T Intellectual Property I, LP
    Inventors: Alan L. Glasser, Andrew G. Gauld, Vijay Gopalakrishnan, John F. Lucas, Kadangode K. Ramakrishnan
  • Publication number: 20120054367
    Abstract: Methods and apparatus to migrate virtual machines between distributive computing networks across a wide area network are disclosed. A disclosed example method includes establishing a data link across a wide area network between a first distributive computing network and a second distributive computing network, the first distributive computing network including a virtual machine operated by a first host communicatively coupled to a virtual private network via a first virtual local area network, communicatively coupling a second host included within the second distributive computing network to the virtual private network via a second virtual local area network, and migrating the virtual machine via the data link by transmitting a memory state of at least one application on the first host to the second host while the at least one application is operating.
    Type: Application
    Filed: August 24, 2010
    Publication date: March 1, 2012
    Inventors: Kadangode K. Ramakrishnan, Jacobus Van Der Merwe, Prashant Shenoy, Timothy Wood
  • Publication number: 20120033582
    Abstract: A method and system are described to multicast with an adaptive dual state. The system receives multicast traffic over a membership tree including a first plurality of nodes connected in a first topology destined for a plurality of multicast members of a first multicast group. Next, the system determines a rate of multicast traffic that exceeds a predetermined threshold based on the receiving the multicast traffic. Next, the system generates a dissemination tree including a second plurality of nodes connected in a second topology to reduce a number of hops to communicate the multicast traffic to the plurality of multicast members of the first multicast group. Finally, the system forwards the multicast traffic to the plurality of multicast members of the first multicast group over the dissemination tree.
    Type: Application
    Filed: October 20, 2011
    Publication date: February 9, 2012
    Applicant: AT & T Intellectual Property I, LP
    Inventors: Kadangode K. Ramakrishnan, Divesh Srivastava, Tae Won Cho, Yin Zhang, Michael Rabinovich