Nokia of America Corporation

Alcatel Lucent

Alcatel

Nokia Solutions and Networks Oy

Alcatel-lucent Canada Inc.

Ehsan Rezaaifar

Fang Hao

T V Lakshman

Murali Kodialam

Hamid Ould-Brahim

Felix Katz

Chuong Ngoc Ngo

Christopher Warren Murray

Andrew W Stone

Reza Mohammad Rokui

Attaullah Zabihi-Seissan

Ebrahim Ghazisaeedi

Rajesh Kumar Paida

Yuri Bassin

This disclosure generally discloses a bidirectional constrained path search mechanism. The bidirectional constrained path search mechanism may be configured to determine bidirectional paths between a pair of nodes, subject to one or more constraints, such that the bidirectional paths share a common set of resources. The bidirectional constrained path search mechanism may be configured to determine bidirectional paths between a pair of nodes, subject to one or more constraints, by determining a forward path that satisfies a set of forward path constraints associated with the forward path and determining a reverse path that satisfies a set of reverse path constraints associated with the reverse path. The bidirectional constrained path search mechanism may be configured to determine bidirectional paths between a pair of nodes in a single path search iteration, such as via a traversal of a weighted directed graph, thereby improving performance.

Bidirectional constrained path search

Various embodiments relate to a non-transitory computer readable medium and method thereof for finding a minimum hop path in a segment graph traversing the least number of links in a physical topology, the method including receiving a connection request for a connection between a source node and a destination node, computing the segment graph, the segment graph having a plurality of links, computing a bandwidth for each of the plurality of links in the segment graph, computing the number of links for a shortest path ('N(q)') for each of the plurality of links, eliminating each of the plurality of link with a bandwidth less than the minimum bandwidth and selecting the shortest path in the physical topology between the plurality of links.

Method and apparatus for minimum label bandwidth guaranteed path for segment routing

The present disclosure discloses improvements in computer performance for supporting traffic steering based on a traffic steering capability. The traffic steering capability may be configured to support steering of traffic of a traffic flow, to be supported by a provider core network, along an end-to-end path between a source ingress provider edge router of the provider core network and a destination outside of the provider core network based on determination of the end-to-end path for the traffic flow (e.g., based on end-to-end path performance measurement information that includes internal path performance measurement information of potential internal paths of the provider core network and external path performance measurement information of potential external paths outside of the provider core network) and programming of the provider core network to support steering of the traffic of the traffic flow onto the end-to-end path for the traffic flow (e.g., based on various types of network programming capabilities).

Traffic steering

Various embodiments relate to a method and apparatus for computing a minimum segment labeling of a given path on a segment cover graph, the method including receiving a connection request for a connection between a source node and a destination node, generating a Shortest Path Directed Acyclic Graph ('SPDAG') from the source node to the destination node by running a shortest path algorithm from the source node, determining an end node, between the source node and the destination node, at which the SPDAG deviates from the given path, determining whether the end node is the end of an Equal Cost Multipath ('ECMP') and terminating the shortest path algorithm at a predecessor node to the end node if the end node is the end of an ECMP and making the predecessor node to the end node the source node.

Method and apparatus for instantiating a path with the minimum number of segments

Routing path calculation apparatus and methods are disclosed. Calculation of routing paths within different routing areas of a communication system is handled by respective routing path calculation devices. Multiple devices may be requested to perform respective routing path calculations for segments of a routing path between endpoints in different routing areas. Recalculations may be requested from the same or different devices in the event of a change in a routing area that affects a segment of a routing path. A routing path calculation device, whether or not in this type of distributed routing path calculation system, may determine whether a previously configured path exists between an intermediate node of a calculated routing path, and take the previously configured path into account in calculating the routing path if it is determined that a previously configured path exists. The previously configured path may be an Interior Gateway Protocol (IGP) shortcut, for example.

Routing path calculation apparatus and methods

A method and associated device for selecting one of a number of equivalent paths in forwarding a network message from a node of a communication network. A source and destination address is provided for the network message. The addresses are formed of individual bit values, and these values have a relative mapping between them. The relative mapping is decorrelated to obtain a decorrelated address pair. A randomized selection function is applied to the decorrelated address pair to produce an index which is derived from the relative sequence of bit values of the decorrelated address paid. The index is then used to select one of the equivalent paths. The associated device provides an address reader, a decorrelation module and a randomized selection module for performing the method previously described.

Equivalent multiple path traffic distribution in communications networks

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Ottawa, Canada

Ehsan Rezaaifar