Lucent Technologies Inc.

The Boeing Company

Alcatel-lucent USA Inc.

Alcatel Lucent

Muhammad A Qureshi

Ramesh Nagarajan

Yung-Terng Wang

Zbigniew M Dziong

Bharat Tarachand Doshi

Wayne Richard Howe

David Brian Lofquist

Xiang Liu

Mooi Choo Chuah

Randy Clinton Giles

Steven Arvo Surek

Vinay Purohit

A method for determining a restoration path for a new service in a mesh network involves selecting between candidate restoration paths corresponding to a primary path for the new service based on the shared-risk link groups (SRLGs) associated with links in the primary path. The method includes, for each of a plurality of candidate restoration paths associated with the primary path, (1) determining whether the primary path requires any additional restoration bandwidth to be reserved on any link of the restoration path based on whether, for each link of the restoration path, the primary path is SRLG-disjoint from each other primary path that is protected by that link, (2) generating a path cost for the restoration path, where the path cost is a function of whether any additional restoration bandwidth is required; and (3) selecting the restoration path for the new service based on the path cost.

Restoration path calculation considering shared-risk link groups in mesh networks

A node in a mobile ad-hoc network or other network classifies packets (a) in accordance with a first set of priority levels based on urgency and (b) within each priority level of the first set, in accordance with a second set of priority levels based on importance. The node: (a) queues packets classified at highest priority levels of the first and/or second sets in high-priority output queues; (b) queues packets classified at medium priority levels of the first set in medium-priority output queue(s); and (3) queues packets classified at low priority levels of the first and/or second set in low-priority output queue(s). Using an output priority scheduler, the node serves the packets in order of the priorities of the output queues. In such manner, orthogonal aspects of DiffServ and MLPP can be resolved in a MANET or other network.

Queuing architectures for orthogonal requirements in quality of service (QoS)

A method for representing, in a network data structure, a minimum amount of protection bandwidth required to be reserved on each link in a mesh network, to restore service upon failure of another node or link in the network. The method includes (1) receiving a request for a new service in the network, wherein the new service is represented by a service data structure having an identification of each link and transit node in a primary path for the new service, (2) determining, using the network and service data structures, whether the new service requires additional protection bandwidth to be reserved on any link in the network, and (3) updating the network data structure if any additional protection bandwidth is determined to be needed. In one implementation the network and service data structures are vectors and the steps of determining and updating involve vector operations between these structures.

Calculation, representation, and maintenance of sharing information in mesh networks

A protected communication network utilizes a link-based recovery strategy that supports independent recovery paths for individual demands, where each link includes one or more lines and each line can support one or more demands. Failure of one or more&#x2014;or even all&#x2014;of the lines/ports of a link will typically result in the independent rerouting of the affected demands along one or more link-detour paths. The flexibility afforded by recovery at the granularity of a demand supports the computation of more-optimal link-detour paths and a corresponding increase in sharing of network resources between disjoint failures. The network also addresses the restricted case where all demands on a line/port are recovered along the same link-detour path.

Link-based recovery with demand granularity in mesh networks

A computer implemented method, apparatus, and computer usable program code for managing addresses in a network. In one advantageous embodiment, a computer implemented method is used to managing addresses for a plurality of destinations in a network. Addresses assigned to a plurality of gateways are summarized to form summarized addresses containing prefixes and addresses for the plurality of gateways in which each gateway in the plurality of gateways is associated with a portion of the prefixes and addresses for destinations handled by the each gateway in the plurality of gateways. A gateway in the plurality of gateways having a largest portion of the summarized addresses is assigned a prefix for all addresses assigned to the network to form a selected gateway. An associated portion of the summarized addresses for the selected gateway is replaced with the prefix.

Method and apparatus for distributing dynamic auto-summarization of internet protocol reachable addresses

A method, apparatus, and computer usable program code for managing networks. In one advantageous embodiment, a computer implemented method processes routing information. The process collects updates to the routing information in a first network. Responsive to an event, a cost of reaching each address in the first network from each of a plurality of gateways in the first network that has access to a second network is identified to form identified costs. The process also selects a set of addresses for a set of gateways providing access to the second network, wherein each gateway in the set of gateways is identified using a policy with respect to a cost of reaching a particular address in the first network to form an update list. The update list is sent to the second network.

Method and apparatus for network routing between a tactical network and a satellite network

An optical transport network comprises a number of nodes, or routers, which are coupled together via optical fibers. When a physical link comes up between a node and a neighboring node, a handshake between the node and the neighboring node recognizes the link such that the node, and the neighboring node, include it in respective link assignment tables. In addition, the node and the neighboring node negotiate a predefined sequence for assigning link resources from their respective assignment tables for satisfying future connection requests.

Minimum contention distributed wavelength assignment in optical transport networks

A method for determining primary and restoration paths for a new service in a mesh network involves (1) for each of a plurality of candidate primary/restoration path pairs for the new service, generating a path cost for each candidate pair, where the path cost for each restoration path is a function of the sum of the cost of links within the restoration path, and (2) selecting the primary and restoration paths for the new service from the plurality of candidate path pairs based on the path cost. If no sharing is possible, for low utilization links, the cost of links is a function of the administrative weight of the link, whereas for high utilization links, the link cost is a function of the inverse of the available capacity on the link. If sharing is possible, the cost is a function of the inverse of a sharing degree for the link.

Primary/restoration path calculation in mesh networks based on multiple-cost criteria

A shared mesh data network (SMDN) for path-based recovery at the packet level. In one implementation, a first link in the network is part of two or more different protection paths, where each protection path corresponds to a different primary path. A network manager determines how much protection bandwidth to reserve on the first link for the two or more protection paths in such a way that the protection bandwidth reserved on the first link is shared between the protection paths of the two or more primary paths. As such, the amount of protection bandwidth reserved on the first link can be less than the sum of the bandwidths of the two or more primary paths. The SMDN provides efficient sharing of protection capacity. Implementations of the SMDN are appropriate to multiprotocol label-switched (MPLS) optical networks.

Sharing restoration path bandwidth in mesh networks

A protected communication network utilizes a link-based recovery strategy that includes methods for calculating and distributing link-protection parameters and calculating primary and link-detour paths based on these parameters. These link-protection parameters support the computation of more-optimal link-detour paths and a corresponding increase in sharing of network resources between disjoint failures. A joint-optimization mechanism can be employed that considers both the cost of link-detour paths as well as the cost of links in candidate primary paths in the selection of a primary path for a demand. Information for the joint optimization is preferably distributed using link-state advertisements.

Calculation of link-detour paths in mesh networks

An extension to a connection setup protocol for establishment of a restoration path for a service in a mesh network involves, at a transit node along the restoration path, the steps of (1) receiving a service data structure having an identification of each link and transit node in a primary path for the service, and (2) determining whether to reserve additional protection bandwidth on an outgoing link incident to the transit node using the service data structure, wherein the outgoing link is part of the restoration path. In one or more embodiments, the service data structure includes identification of the service, identification of the outgoing link, and bandwidth of the service. In some cases, the extension involves reserving the additional protection bandwidth on the outgoing link, if the transit node determines that the protection bandwidth is required, based upon knowledge of the protection bandwidth already reserved on the outgoing link.

Connection set-up extension for restoration path establishment in mesh networks

In a packet-based data network, packets are duplicated and a sequence number is inserted into each duplicate packet, where the duplicate packets are transmitted along two different paths from a source node to a destination node in the network. Depending on the implementation, the source node inserts different types of sequence numbers into the duplicate packets, and the destination node processes those sequence numbers accordingly to determine whether to accept or reject each received packet. In certain implementations, the number of sequence bits allocated to each packet is smaller than the size of the effective sequence number for the packet as interpreted by the destination node.

Sequence number schemes for acceptance/rejection of duplicated packets in a packet-based data network

In a network architecture, selective grooming is performed. In selective grooming, a low traffic node is coupled (a) directly to an other low traffic node via a high capacity trunk, and (b) to a high traffic node via a high capacity trunk such that only a portion of the client signals destined for the other low traffic node are groomed into the high capacity trunk to the high traffic node.

Traffic grooming methods for undersea trunk and branch architectures

Method and apparatus for routing messages in a network includes first filters to provide frequency-based message signals converted from an optically-based signal and mixers adapted to mix the frequency-based message signals with sub-carriers to generate frequency-based sub-carrier modulated message signals. A frequency generator connected to the mixers provides the sub-carriers to the mixers and a combiner connected to the mixers combines the frequency-based sub-carrier modulated message signals. Second filters connected to the combiner receive and group the frequency-based sub-carrier modulated message signals. Optical transmitters connected to second filters optically convert and transmit the frequency-based sub-carrier modulated message signals. The frequency generator generates and applies a particular sub-carrier frequency to one of the mixers according to information contained in the frequency-based message signal. The information is encoded into the frequency-based message signal via a generalized MPLS (GMPLS) label contained in a header portion of the frequency-based message signal.

Growing community of inventors

Green Brook, NJ, United States of America

Muhammad A Qureshi