Pankaj Risbood

US Patent:

7397815, Jul 8, 2008

Filed:

Jan 27, 2005

Appl. No.:

11/044974

Inventors:

Bhawna Gupta - Whitehouse Station NJ, US
Pankaj Risbood - Roselle NJ, US

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

H04L 12/43

US Classification:

370458, 370907

Abstract:

Techniques for defragmenting at least one time division multiplexed link in a communication system, wherein provisioned circuits corresponding to traffic demands are assigned to particular time slots of the link. An optimum layout of free space for the link is computed, subject to an interface rate constraint that may be specified as a minimum cross-connect rate and a maximum cross-connect rate. Particular free slots from the optimum layout of free space are selected, and a hitless migration sequence is determined for migrating one or more of the circuits to one or more of the selected free slots. The time slot assignments of one or more of the circuits are adjusted in accordance with the determined migration, sequence in order to defragment the link.

US Patent:

7408881, Aug 5, 2008

Filed:

Sep 24, 2004

Appl. No.:

10/949638

Inventors:

Swarup Acharya - New Providence NJ, US
Pankaj Risbood - Roselle NJ, US
Anurag Srivastava - Roselle NJ, US

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

H04J 1/116

US Classification:

370238, 370228, 709241

Abstract:

Virtually-concatenated data traffic is routed in a network comprising a plurality of nodes. For a given traffic demand to be routed from a source node to a destination node in the network, an initial candidate path set satisfying a differential delay constraint is determined by arranging a plurality of paths in order of increasing delay and selecting a particular subset of the plurality of paths as the initial candidate set. A determination is then made as to whether the initial candidate path set is able to support a bandwidth requirement of the traffic demand. If the initial candidate path set is able to support the bandwidth requirement of the traffic demand, the initial candidate path set is utilized to route the traffic demand. Otherwise, the process is repeated for one or more additional iterations, with a different candidate path set satisfying the differential delay constraint being selected for a given additional iteration by application of a sliding-window function to the plurality of paths arranged in order of increasing delay, until a different candidate path satisfying the differential delay constraint is determined to support the bandwidth requirement of the traffic demand.

US Patent:

7411900, Aug 12, 2008

Filed:

May 28, 2003

Appl. No.:

10/446220

Inventors:

Swarup Acharya - New Providence NJ, US
Bhawna Gupta - Edison NJ, US
Pankaj Risbood - Roselle NJ, US
Anurag Srivastava - Roselle NJ, US

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

G01R 31/08

US Classification:

370217, 370907

Abstract:

Techniques are disclosed for restoration of virtually-concatenated data traffic in a data transmission network. A virtually-concatenated group is formed comprising: (i) a plurality of primary members each associated with a corresponding data stream, and (ii) at least one backup member. Each of the plurality of primary members and the backup member of the virtually-concatenated group may be assigned a corresponding one of a plurality of data transmission routes between first and second nodes of the network. Responsive to a failure of a given one of the plurality of primary members, the backup member is utilized for restoring at least a portion of the data traffic of the given member. The invention also provides a modified link capacity adjustment scheme (LCAS) protocol which substantially reduces the time required to report changes in member status information from a sink node to a source node, thereby substantially reducing the amount of time required to perform a restoration operation.

US Patent:

7426186, Sep 16, 2008

Filed:

Jan 16, 2003

Appl. No.:

10/345612

Inventors:

Swarup Acharya - New Providence NJ, US
Bhawna Gupta - Edison NJ, US
Pankaj Risbood - Roselle NJ, US
Anurag Srivastava - Roselle NJ, US

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

G01R 31/08

US Classification:

370238, 370252, 370255, 370401

Abstract:

A method for data path provisioning in a reconfigurable data network is disclosed. A data path between a source IP router and a destination IP router is determined taking into account the IP-subnets of the network interfaces of the IP routers included in the path. In one embodiment, the requirement that two IP routers can send packets via their connected interface if and only if the two interfaces are on the same subnet (i. e. , the subnet constraint) is completely honored during the data path determination. In another embodiment, the data path is determined while allowing some number of violations of the subnet constraint. A transform network graph is computed and is used to determine the data path taking into account the IP-subnets.

US Patent:

7518990, Apr 14, 2009

Filed:

Dec 26, 2003

Appl. No.:

10/745881

Inventors:

Swarup Acharya - New Providence NJ, US
Bhawna Gupta - Edison NJ, US
Pankaj Risbood - Roselle NJ, US
Anurag Srivastava - Roselle NJ, US

Assignee:

Alcatel Lucent USA Inc. - Murray Hill NJ

International Classification:

G01R 31/08

US Classification:

370225, 370235, 3703954, 370468

Abstract:

Virtually-concatenated data traffic is routed in a network comprising at least first and second nodes. The first and second nodes may comprise a source-sink node pair, an ingress-egress node pair, or any other pair of network nodes. For a given traffic demand, a plurality of routes for routing the traffic demand through the network are determined. Each of the routes corresponds to a member of a virtually-concatenated group, such that different portions of the traffic demand are assigned to different members of the virtually-concatenated group.

US Patent:

7660525, Feb 9, 2010

Filed:

Feb 25, 2005

Appl. No.:

11/065839

Inventors:

Pankaj Risbood - Roselle NJ, US

Assignee:

Alcatel-Lucent USA Inc. - Murray Hill NJ

International Classification:

H04J 14/02

US Classification:

398 4, 398 59, 398 69

Abstract:

Techniques are disclosed for generating a hitless migration plan to optimal state, given an optimal routing and wavelength assignment for demands. For example, a technique for use in performing a circuit transition in accordance with an optical ring-based network comprises the following steps/operations. First, a first (e. g. , initial) circuit layout and a second (e. g. , final) circuit layout for a given set of demands to be routed on the optical ring-based network are obtained. Then, a minimum number of free wavelengths required to transition the network from the first circuit layout to the second circuit layout is determined such that substantially no network service disruption occurs due to the circuit transition.

US Patent:

7813270, Oct 12, 2010

Filed:

May 15, 2003

Appl. No.:

10/438431

Inventors:

Swarup Acharya - New Providence NJ, US
Bhawna Gupta - Edison NJ, US
Pankaj Risbood - Roselle NJ, US
Anurag Srivastava - Roselle NJ, US

Assignee:

Alcatel-Lucent USA Inc. - Murray Hill NJ

International Classification:

H04J 1/16

US Classification:

370225, 370238, 370252

Abstract:

A maximum-flow based route precomputation algorithm includes at least a route generation phase and a route selection phase, and determines one or more routes between at least a given pair of nodes in a network. In the route generation phase, a maximum-flow algorithm is applied to a first set of information characterizing links between the given pair of nodes in the network. The output of the maximum-flow algorithm is utilizable to generate a second set of information characterizing corresponding admissible flows. In the route selection phase, one or more routes are determined based on the second set of information using, for example, a shortest widest path (SWP) algorithm. The route generation and route selection phases may be repeated for each of a plurality of node pairs of the network.

US Patent:

7864690, Jan 4, 2011

Filed:

Aug 8, 2003

Appl. No.:

10/637289

Inventors:

Swarup Acharya - New Providence NJ, US
Bhawna Gupta - Edison NJ, US
Pankaj Risbood - Roselle NJ, US
Anurag Srivastava - Roselle NJ, US

Assignee:

Alcatel-Lucent USA Inc. - Murray Hill NJ

International Classification:

H04L 1/00

US Classification:

370248, 370222, 370228, 370258

Abstract:

A system and method for rerouting circuits on a SONET, SDH or similar ring without disrupting service. In one embodiment, the system includes: (1) a route design subsystem adapted to identify, for the circuits, alternative routes that are subject to an alignment constraint and increase an objective value associated with the ring and (2) a path migration subsystem, associated with the route design subsystem, adapted to determine a hitless migration sequence that allows the alternative routes to be employed.