Patents by Inventor Tirunell V. Lakshman

Tirunell V. Lakshman 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: 8018940
    Abstract: In one embodiment, IP lookup into a routing table having prefixes of different prefix lengths is performed using a Bloom filter that was programmed with the prefixes corresponding to all of the different prefix lengths without having to expand any of the prefixes programmed into the Bloom filter. Membership probes are performed into the Bloom filter using candidate prefix values of a given network address. The Bloom filter can be implemented in a distributed manner using Bloom sub-filters, where each Bloom sub-filter is hashed based on a set of hash functions, where each different hash function in the set corresponds to a different prefix length in the routing table. Each Bloom sub-filter can in turn be implemented using a plurality of practically realizable multi-port memory devices controlled by a port scheduler. False-positive matches can be detected and next-hop information for true-positive matches retrieved using an off-chip, hash-based prefix table.
    Type: Grant
    Filed: August 13, 2008
    Date of Patent: September 13, 2011
    Assignee: Alcatel Lucent
    Inventors: Fang Hao, Muralidharan S. Kodialam, Tirunell V. Lakshman, Haoyu Song
  • Patent number: 7978594
    Abstract: In one embodiment, a method for supporting recovery from failure of a link in a network of nodes interconnected by links. An intermediate node between an ingress point and an egress point of the network is selected to minimize the sum of (i) a capacity constraint between the ingress point and the intermediate node and (ii) a capacity constraint between the intermediate node and the egress point. The selection identifies two path structures, each comprising a primary path and one or more link backup detours protecting each link on the primary path, with a first path structure between the ingress point and the intermediate node, and a second path structure between the intermediate node and the egress point. To maximize network throughput, packets are routed in two phases, first to the intermediate node via the first path structure in predetermined proportions, and then from the intermediate node to the final destination via the second path structure.
    Type: Grant
    Filed: May 31, 2005
    Date of Patent: July 12, 2011
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Muralidharan S. Kodialam, Tirunell V. Lakshman, Sudipta Sengupta
  • Patent number: 7961731
    Abstract: A method for measuring flow is disclosed. The method includes receiving an IP packet; determining if another IP packet is stored in a register; if another IP packet is stored in the register, comparing the stored IP packet with the received IP packet; and determining the longest match between the stored IP packet and the received IP packet.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: June 14, 2011
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Fang Hao, Muralidharan Sampath Kodialam, Tirunell V. Lakshman
  • Patent number: 7957266
    Abstract: A scheme for routing packets of traffic to their destination after ensuring that they pass through one or more pre-determined intermediate nodes, thereby permitting all permissible traffic patterns to be handled without knowledge of the traffic matrix, subject to edge-link capacity constraints. In one embodiment, a request for a path with a service demand for routing data between the ingress point and the egress point is received. A set of two or more intermediate nodes between the ingress point and the egress point is selected. Based on a bandwidth of the network, respective fractions of the data to send from the ingress point to each node of the set of intermediate nodes are determined. The data is routed in the determined respective fractions from the ingress point to each node of the set of intermediate nodes, and routed from each node of the set of intermediate nodes to the egress point.
    Type: Grant
    Filed: April 14, 2005
    Date of Patent: June 7, 2011
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Muralidharan S. Kodialam, Tirunell V. Lakshman, Sudipta Sengupta
  • Patent number: 7957272
    Abstract: The invention includes a method and apparatus for determining a coincidence count associated with a traffic flow in a network. The method includes receiving a first packet having a first flow identifier associated with one of the traffic flows, comparing the first flow identifier of the first packet to each of a plurality of other flow identifiers associated with a respective plurality of other packets, and determining a coincidence count associated with the first flow identifier based on the comparison of the first flow identifier to each of the plurality of other flow identifiers. The method for determining a coincidence count associated with one of a plurality of traffic flows may be extended for determining respective coincidence counts associated with a plurality of traffic flows. The determined coincidence counts may be used for determining at least one traffic flow statistic.
    Type: Grant
    Filed: March 10, 2006
    Date of Patent: June 7, 2011
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Fang Hao, Muralidharan Sampath Kodialam, Tirunell V. Lakshman, Hui Zhang
  • Patent number: 7930547
    Abstract: A method and system for generating a bloom filter by mapping into respective groups each of a plurality of initial keys according to a first hash function and mapping each group hashed key into a bloom filter using k respective hash functions.
    Type: Grant
    Filed: June 15, 2007
    Date of Patent: April 19, 2011
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Fang Hao, Muralidharan Sampath Kodialam, Tirunell V. Lakshman
  • Publication number: 20110016206
    Abstract: Example methods include monitoring Internet traffic for a user, analyzing content of the Internet traffic, correlating the analyzed content with a simplified classifier set, ranking each correlated simplified classifier in the simplified classifier set, and storing the ranked simplified classifiers in a user interest profile for the user. Customer premise equipment may include a residential gateway, such as a wireless router, and user equipment such as a personal computer. Example systems may be configured from customer premise equipment or Internet service providers to generate user interest profiles in accordance with example methods.
    Type: Application
    Filed: July 15, 2009
    Publication date: January 20, 2011
    Inventors: Muralidharan Sampath Kodialam, Tirunell V. Lakshman, Sarit Mukherjee, Limin Wang
  • Publication number: 20100329133
    Abstract: Method and apparatus using incremental linear regression to derive a traffic flow signature indicative of a particular application within a packet stream.
    Type: Application
    Filed: June 30, 2009
    Publication date: December 30, 2010
    Inventors: Fang Hao, Muralidharan Sampath Kodialam, Tirunell V. Lakshman
  • Publication number: 20100266215
    Abstract: A variable-stride multi-pattern matching apparatus segments patterns and input streams into variable-size blocks according to a modified winnowing algorithm. The variable-stride pattern segments are used to determine the block-symbol alphabet for a variable-stride discrete finite automaton (VS-DFA) that is used for detecting the patterns in the input streams. Applications include network-intrusion detection and protection systems, genome matching, and forensics. The modification of the winnowing algorithm includes using special hash values to determine the position of delimiters of the patterns and input streams. The delimiters mark the beginnings and ends of the segments. In various embodiments, the patterns are segmented into head, core, and tail blocks. The approach provides for memory, memory-bandwidth, and processor-cycle efficient, deterministic, high-speed, line-rate pattern matching.
    Type: Application
    Filed: April 17, 2009
    Publication date: October 21, 2010
    Applicant: ALCATEL-LUCENT USA INC.
    Inventors: Nan Hua, Tirunell V. Lakshman, Haoyu Song
  • Publication number: 20100269024
    Abstract: A method and apparatus providing improved set membership determination and group membership identification of candidate data elements using a single Bloom filter programmed to provide a plurality of non-zero f-bit binary vectors, where each of the f-bit binary vectors is associated with a respective group. The Bloom filter is programmed using one or more (but not all) of a plurality of hash filter sets.
    Type: Application
    Filed: April 18, 2009
    Publication date: October 21, 2010
    Inventors: Fang Hao, Muralidharan Sampath Kodialam, Tirunell V. Lakshman, Haoyu Song
  • Patent number: 7808923
    Abstract: In one embodiment, a node-implemented method for performing analysis of traffic within a packet communications network. First, the node measures a traffic aggregate at specified nodes within the network with regard to a packet set of interest. Each traffic aggregate (i) is a set of packets, observed at one of the specified nodes, having a common characteristic and (ii) is measured at one of the specified nodes by creating a digest for the packets having the common characteristic. The digest characterizes the traffic aggregate without containing the actual packets themselves. Next, the node formulates an intersection set cardinality determination for a network traffic-characterizing parameter to be measured in the network utilizing the digests characterizing the traffic aggregates. Next, the node solves the set cardinality determination for the network traffic-characterizing parameter to be measured.
    Type: Grant
    Filed: May 23, 2008
    Date of Patent: October 5, 2010
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Muralidharan S. Kodialam, Tirunell V. Lakshman, Wing Cheong Lau
  • Publication number: 20100251290
    Abstract: In one embodiment, a scheme for the display of targeted and personalized advertisements in a packet-based media-delivery system, such as an Internet Protocol Television (IPTV) service. An Internet keyword-based advertisement-bidding model is used to place the most-appropriate IPTV advertisements for viewers depending on their interests as determined through the users' Internet activities, while maximizing advertising revenue for the IPTV service provider. One method for scheduling an advertisement for rendering in one or more time slots in packet-based media programming comprises: (a) obtaining at least one keyword from one or more Internet sessions corresponding to at least one user; (b) receiving a plurality of bid amounts corresponding to a plurality of available advertisements for the one or more time slots; and (c) scheduling, based on the at least one keyword and at least one of the bid amounts, the advertisement to be rendered to the at least one user in the one or more time slots.
    Type: Application
    Filed: March 31, 2009
    Publication date: September 30, 2010
    Applicant: Alcatel-Lucent USA Inc.
    Inventors: Muralidharan S. Kodialam, Tirunell V. Lakshman, Sarit Mukherjee
  • Patent number: 7729257
    Abstract: The invention includes a method and apparatus for generating a link transmission schedule for handling traffic variation in wireless networks without dynamic scheduling or routing. The method includes determining fixed traffic capacities associated with respective wireless links of a wireless network according to a routing algorithm, and generating, using the routing algorithm and the fixed traffic capacities, a link transmission schedule including at least one condition by which traffic is transmitted using each of the network links. The link transmission schedule is adapted to remain substantially fixed during dynamic traffic changes. The routing algorithm may be a two-phase routing algorithm in which traffic is distributed by each node in the wireless network to every node in the wireless network using traffic split ratios.
    Type: Grant
    Filed: March 30, 2006
    Date of Patent: June 1, 2010
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Muralidharan Sampath Kodialam, Tirunell V. Lakshman, Sudipta Sengupta
  • Patent number: 7715382
    Abstract: The SoftRouter architecture separates the implementation of control plane functions from packet forwarding functions. In this architecture, all control plane functions are implemented on general purpose servers called the control elements (CEs) that may be multiple hops away from the forwarding elements (FEs). A network element (NE) or a router is formed using dynamic binding between the CEs and the FEs. The flexibility of the SoftRouter architecture over conventional routers with collocated and tightly integrated control and forwarding functions results in increased reliability, increased scalability, increased security, ease of adding new functionality, and decreased cost.
    Type: Grant
    Filed: June 8, 2005
    Date of Patent: May 11, 2010
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Tirunell V. Lakshman, Thyagarajan Nandagopal, Ramachandran Ramjee, Krishan K. Sabnani, Thomas Y. Woo
  • Patent number: 7710953
    Abstract: The invention includes an apparatus and method for switching packets through a switching fabric. The apparatus includes a plurality of input ports and output ports for receiving arriving packets and transmitting departing packets, a switching fabric for switching packets from the input ports to the output ports, and a plurality of schedulers controlling switching of packets through the switching fabric. The switching fabric includes a plurality of virtual output queues associated with a respective plurality of input-output port pairs. One of the schedulers is active during each of a plurality of timeslots. The one of the schedulers active during a current timeslot provides a packet schedule to the switching fabric for switching packets through the switching fabric during the current timeslot.
    Type: Grant
    Filed: March 30, 2007
    Date of Patent: May 4, 2010
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Muralidharan Sampath Kodialam, Tirunell V. Lakshman
  • Publication number: 20100069074
    Abstract: In one embodiment, a wireless-resource broker employs a self-enforcing spectrum-sharing policy, e.g., the expected utility (e.g., rate) a user obtains by following the policy provided by the broker is not less than the expected utility that the user obtains by switching to some other strategy. Each user is associated with one or more transmitter-receiver pairs, e.g., a transmitter of a wireless device and a receiver of a base station in communication via a wireless channel. The broker receives, as input, user parameters characterizing one or more of the transmitters and/or receivers and resource parameters characterizing one or more available spectrum blocks. The broker solves a linear-programming problem to generate and transmit a recommended policy for one or more users. The policy for each user includes information such as the spectrum block(s) to which the user is assigned, the transmission power for the user, and the transmission rate for the user.
    Type: Application
    Filed: September 12, 2008
    Publication date: March 18, 2010
    Applicant: Lucent Technologies Inc.
    Inventors: Muralidharan S. Kodialam, Tirunell V. Lakshman
  • Publication number: 20100040066
    Abstract: In one embodiment, IP lookup into a routing table having prefixes of different prefix lengths is performed using a Bloom filter that was programmed with the prefixes corresponding to all of the different prefix lengths without having to expand any of the prefixes programmed into the Bloom filter. Membership probes are performed into the Bloom filter using candidate prefix values of a given network address. The Bloom filter can be implemented in a distributed manner using Bloom sub-filters, where each Bloom sub-filter is hashed based on a set of hash functions, where each different hash function in the set corresponds to a different prefix length in the routing table. Each Bloom sub-filter can in turn be implemented using a plurality of practically realizable multi-port memory devices controlled by a port scheduler. False-positive matches can be detected and next-hop information for true-positive matches retrieved using an off-chip, hash-based prefix table.
    Type: Application
    Filed: August 13, 2008
    Publication date: February 18, 2010
    Applicant: Lucent Technologies Inc.
    Inventors: Fang Hao, Muralidharan S. Kodialam, Tirunell V. Lakshman, Haoyu Song
  • Patent number: 7653007
    Abstract: A method of estimating per-flow traffic in a network of nodes interconnected by links samples an incoming traffic stream to a node. A sampling interval is derived based on a desired level of accuracy. The number of two-run occurrences for each flow is tracked in the sample stream. The number of two-runs per flow is then employed to generate an estimate of the traffic of the flow.
    Type: Grant
    Filed: September 22, 2004
    Date of Patent: January 26, 2010
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Muralidharan S. Kodialam, Tirunell V. Lakshman
  • Patent number: 7639611
    Abstract: The invention includes a method and apparatus for generating a coincidence count table adapted for determining at least one flow statistic. The method includes receiving a plurality of packets comprising a respective plurality of payloads, comparing payloads associated with consecutive ones of the plurality of packets for identifying at least one simple pattern included within the compared payloads of the consecutive ones of the plurality of packets, for each of the consecutive ones of the plurality of packets, if the at least one simple pattern is identified, processing the at least one simple pattern to form a complex pattern, and for each complex pattern, updating a coincidence count associated with the complex pattern, wherein the coincidence counts are adapted for determining at least one flow statistic.
    Type: Grant
    Filed: March 10, 2006
    Date of Patent: December 29, 2009
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Fang Hao, Muralidharan Sampath Kodialam, Tirunell V. Lakshman, Hui Zhang
  • Patent number: 7633867
    Abstract: Capacity design of an optical network for demands of connections forms a linear programming sizing problem for a optimal routing. A dual of the linear programming sizing problem is formed and solved with an approximation algorithm. Edge lengths are initialized based on i) the inverse of the edge's capacity and ii) a scalar constant. Then, the approximation algorithm proceeds in phases to route each commodity over the edges of a graph. During each phase, the demand's flow is sent from the source to destination via multiple iterations. During each iteration, the shortest length-bounded path from the source to the destination is determined, a portion of the flow is sent, and the lengths of the edges that carry the flow are updated. The value employed to scale the network is generated after the last phase from the maximum ratio of edge flow to edge capacity.
    Type: Grant
    Filed: February 4, 2003
    Date of Patent: December 15, 2009
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Muralidharan S. Kodialam, Tirunell V. Lakshman