Abstract: Aspects of the invention relate to a method of adapting an association of physical resources in a network with a summarized resource corresponding to one or more class of service. The method comprises monitoring at least one parameter of the summarized resources. The method further comprises comparing the at least one parameter between a plurality of summarized resources, and comparing the class of service of the summarized resources. Based on the comparing of the at least one parameter and based on the comparing of the class of service of the summarized resources, the method comprises determining one or more summarized resources to be a source for providing physical resources and determining one or more summarized resources to be a destination for receiving physical resources. Based on the determining, the method comprises modifying an allocation of physical resources to transfer an association of physical resources from the source summarized resource to the destination summarized resource.

Abstract: The present proposal provides a specific solution for communications network topology summarization with a good trade-off between high scalability, good stability and resources utilization efficiency.

Abstract: Aspects of the invention relate to a method of adapting an association of physical resources in a network with a summarized resource corresponding to one or more class of service. The method comprises monitoring at least one parameter of the summarized resources. The method further comprises comparing the at least one parameter between a plurality of summarized resources, and comparing the class of service of the summarized resources. Based on the comparing of the at least one parameter and based on the comparing of the class of service of the summarized resources, the method comprises determining one or more summarized resources to be a source for providing physical resources and determining one or more summarized resources to be a destination for receiving physical resources. Based on the determining, the method comprises modifying an allocation of physical resources to transfer an association of physical resources from the source summarized resource to the destination summarized resource.

Abstract: A node 800 of a multi-layer communication is capable of routing a message signal via one or more different layers (for example a PSC layer, TDM layer, LSC layer) in the multi-layer communication network. The node 800 comprises a first interface 801 for receiving a path message 803 containing routing information for routing an associated message signal through the multi-layer communication network. One or more second interfaces 805i to 805N are provided for transmitting a message signal to one or more respective layers in the multi-layer communication network. A processing unit 807 is adapted to determine if the path message 803 contains protection information 40 indicating that protection switching is to be performed in one or more different layers of the multi-layer communication network, and if so, establish a protection switching mechanism in the one or more different layers using the protection information 40 provided in the path message 803.

Abstract: A path computation element for a communications network, receives link advertisements from hybrid nodes (10) of the network and selects paths for new traffic flows based on the received link advertisements. The hybrid node has switching matrices (20, 30) operable using different protocols, and has internal links between the switching matrices. The link advertisements indicate a maximum and in a minimum bandwidth on any one of the internal links for a new traffic flow. The element can select a path via the hybrid node for a new traffic flow according to the bandwidth of the requested new traffic flow and according to the maximum and the minimum bandwidth indicated by the link advertisements. Advertising the maximum and minimum bandwidths available for a single new traffic flow for the internal links can enable more efficient path computation with little additional cost and hence maintain scalability of the link advertisements for larger networks.

Abstract: The present proposal provides a specific solution for communications network topology summarization with a good trade-off between high scalability, good stability and resources utilization efficiency.

Abstract: A node 800 of a multi-layer communication is capable of routing a message signal via one or more different layers (for example a PSC layer, TDM layer, LSC layer) in the multi-layer communication network. The node 800 comprises a first interface 801 for receiving a path message 803 containing routing information for routing an associated message signal through the multi-layer communication network. One or more second interfaces 805i to 805N are provided for transmitting a message signal to one or more respective layers in the multi-layer communication network. A processing unit 807 is adapted to determine if the path message 803 contains protection information 40 indicating that protection switching is to be performed in one or more different layers of the multi-layer communication network, and if so, establish a protection switching mechanism in the one or more different layers using the protection information 40 provided in the path message 803.

Abstract: According to a first aspect of the present invention there is provided a method of constructing an end-to-end routing path across multiple packet switched domains. The method comprises generating a domains topology identifying all possible domains, the border elements of those domains and the inter-domain links. When a request is received for computation of a path from a source entity in a first domain to a destination entity in a second domain, all domains and inter-domain links that cannot or are unlikely to feature in the requested path are removed from the domains topology. Candidate intra-domain paths for each remaining domain are then computed, with each candidate intra-domain path being mapped to a logical link defined by its two ends, at least one end being a border element and the other being a border element or the source or destination entity. Attributes for each logical link are determined, together with attributes of the remaining inter-domain links.

Abstract: A path computation element for a communications network, receives link advertisements from hybrid nodes (10) of the network and selects paths for new traffic flows based on the received link advertisements. The hybrid node has switching matrices (20, 30) operable using different protocols, and has internal links between the switching matrices. The link advertisements indicate a maximum and in a minimum bandwidth on any one of the internal links for a new traffic flow. The element can select a path via the hybrid node for a new traffic flow according to the bandwidth of the requested new traffic flow and according to the maximum and the minimum bandwidth indicated by the link advertisements. Advertising the maximum and minimum bandwidths available for a single new traffic flow for the internal links can enable more efficient path computation with little additional cost and hence maintain scalability of the link advertisements for larger networks.

Abstract: According to a first aspect of the present invention there is provided a method of constructing an end-to-end routing path across multiple packet switched domains. The method comprises generating a domains topology identifying all possible domains, the border elements of those domains and the inter-domain links. When a request is received for computation of a path from a source entity in a first domain to a destination entity in a second domain, all domains and inter-domain links that cannot or are unlikely to feature in the requested path are removed from the domains topology. Candidate intra-domain paths for each remaining domain are then computed, with each candidate intra-domain path being mapped to a logical link defined by its two ends, at least one end being a border element and the other being a border element or the source or destination entity. Attributes for each logical link are determined, together with attributes of the remaining inter-domain links.