Abstract: A method and system for supporting roaming broadband services. The method is implemented by a computing device in a parent provider network of a user having a unique user identifier to enable the user to utilize services associated with a broadband access service contract of the user of the parent provider network in a visited location in the parent provider network or in a roaming provider network. The method includes receiving a registration request from the user, determining the unique user identifier for the user, determining services for the user based on the unique user identifier, determining whether the user is connected to a home customer premise equipment (CPE) in the parent provider network, and configuring services and resources at a local data center in the parent provider network, in response to the user being connected to the visited location in the parent provider network.

Abstract: It is disclosed a coordinator (22), a physical network controller (24, 26) and methods therein for enabling end-point mobility of a traffic engineering, TE, tunnel in a multi-domain network. Based on a request for virtual network configuration of one or both of the ingress and the egress end-points of the TE tunnel, the coordinator of a multi-domain network determines 54, S416 a second request for virtualizing said one or both of the ingress and the egress end-points of the TE tunnel. The physical network controller may then virtualize end-points of the TE tunnel, providing a virtualized end-point, VEP, TE tunnel, having end-point mobility capacity. Recovery mechanisms of tunnel paths may be efficiently implemented. The present disclosure also provides scalability improvements and operational expenditure, OPEX, savings, as compared to state of art TE tunnels.

Abstract: Methods for segment routing in a software-defined networking (SDN) system are disclosed. In one embodiment, a method includes receiving a plurality of values of maximum segment identifier (SID) depths, each from one network element of the SDN system, and identifying a path for a packet to transmit through a plurality of network elements, where a plurality of SIDs corresponding to the plurality of network elements is ordered to represent the path. The method further includes splitting the path into a plurality of sub-paths based on the values of the maximum SID depths of the plurality of network elements, where each network element, for the path, is allocated to process a number of ordered SIDs, and where the number is within the network element's maximum SID depth, and causing packet forwarding of the packet along the plurality of sub-paths based on SIDs allocated to the network elements.

Abstract: A method for routing packet traffic through a network comprising a plurality of network nodes supporting RSVP-TE protocol and Segment Routing protocol. Each of the two protocols is associated with a separate set of labels, the method comprises calculating (202) a path through the network; checking support (204) for both protocols at nodes along the calculated path and encoding (206) the calculated path as a set of Adjacency Segment Identifiers. The method also comprises optimising (208) a label stack of the calculated path by substituting more than one adjacency SIDs with a node SID if a partial path identified by the substituted adjacency SIDs equals a shortest path. If all nodes along the calculated path support label stack depth equal to or deeper than the optimised label stack (210) then segment routing is used to set up the path.

Abstract: Distributed management of analytics tasks in a programmable network (100) having a controller (SDNC, 10, 11), a plurality of network nodes (20, N1-N5) coupled to the controller by a Data Communications Network DCN, and a plurality of analytics servers (30) each coupled to a network node, involves the controller selecting which of the analytics servers to use for an analytics task. The selection is based on how data logged by respective ones of the network nodes and needed for that analytics task, can be routed to the analytics servers. The controller sends to the selected analytics server, an indication of the analytics task and an indication of what data logged by the network nodes is to be used in the analytics task.

Abstract: Apparatus and methods are provided for scheduling services in a traffic-engineered communications network. In one aspect a method comprises: receiving a request to schedule a second service utilizing the network in a second time period, wherein the second time period overlaps a first time period in which a first service utilizing the network has already been scheduled; and computing a path for the second service through the network. The step of computing the path for the second service through the network comprises: responsive to a determination that the request is received less than the threshold period of time before the start of the first time period, disallowing the second service from pre-empting the first service.

Abstract: Embodiments include methods of controlling a client layer of a multi-layer communication network that also includes a server layer. Such methods include receiving, at a client physical network controller (PNC), an indication of at least one characteristic associated with one or more paths between server network nodes in the server layer. The indication is received from a multi-domain service controller (MDSC) in the multi-layer communication network, and the server layer is controlled by a server PNC. Such methods include, based on the at least one characteristic, computing one or more paths in the client layer that facilitate protection and/or restoration for the one or more paths in the server layer. Other embodiments include complementary methods performed by a MDSC, as well as client PNCs and MDSCs configured to perform such methods.

Abstract: A path computation method for use by a control entity (20) of a tenant (11) in a multi-tenant communications network (40) receives a request for computation of a path in the communications network (40) and obtains a current virtual topology of the communications network from a shared topology store (31) which is shared by the tenants. The virtual topology is a topology of the communications network which is available for use by the tenant (11). The virtual topology is used to service the request. The method may create the path. The path computation may be in respect of a future time interval.

Abstract: Methods and apparatus are provided for locating a fault in an optical communication link. In one aspect, a method comprises determining a fault in a first optical link, and determining a fault in a second optical link. The method then determines that a first portion of the first optical link is co-located with a second portion of the second optical link and identifies, as a result of determining that the first portion is co-located with the second portion, that the fault in the first optical link is located in the first portion and/or the fault in the second optical link is located in the second portion.

Abstract: A method in a controller node for performing segment routing in a non-packet data network comprising a plurality of nodes, comprises receiving information relating to the topology of the non-packet data network connecting the plurality of nodes, the non-packet data network forming a data plane network. The method comprises computing a segment routing path to be taken for non-packet traffic data through the data plane network, wherein the segment routing path is computed using segment identifiers, SIDs, relating to a data communication network, DCN, coupled to the plurality of nodes. The method comprises sending the computed segment routing path to an ingress node of the data plane network.

Abstract: Aspects provide a method (10, 100, 150, 160) of controlling a multi-layer communication network comprising a client network and a server network. The method comprises obtaining (12;164) from the server network at least one path characteristic for a path in the server network between server network nodes; and providing (14, 152, 166) to the client network an indication of the at least one path characteristic of the server network.

Abstract: A method of providing state synchronization between a controller and a switch in a communications network, wherein the controller provides flow data for routing flows through the switch and transmits, in flow modification messages, the flow data to the switch for storage in flow tables, the state synchronization comprising ensuring that flow data in the flow tables of the switch are consistent with the flow data provided by the controller. The method comprises, by the controller (19), providing (21) an identifier in each flow modification message.

Abstract: A method and a network node for managing allocation of network resources in restoration of traffic in a connection oriented network are disclosed. The method comprises restoring a first traffic from a first path on an alternative path if the first path is affected by a first failure and assigning a reserved status to resources of the first path no longer used for carrying the first traffic. If a second path is affected by a second failure the method comprises restoring a second traffic from the second path, wherein the restoration of the second traffic does not use the resources having the reserved status.

Abstract: Apparatus and methods are provided for path computation for a service in a telecommunications network. In one aspect, a method comprises receiving a request to schedule the service utilizing the network in a time period determining that a path for the service is not available for the whole of the time period, and determining a plurality of paths for the service, each of the plurality of paths being available during a respective portion of the time period, such that at least one of the plurality of paths is available for the service at any time during the time period.

Abstract: A path computation method involves receiving (200) a request fir computation of a new path in the network, the request indicating a future time interval when the path is desired. Subsequently a future network status is generated (210, 212, 214), having a representation of availability of path resources at the future time interval, based on selected paths already reserved at that future time interval. Then there is a step of computing (220) which of the path resources to select for the new path according to the future network status. By generating this future network status when the time interval is known, it can be generated in respect of a limited time interval rather than covering all possible future reservable times. Thus the benefits of time aware path computation can be achieved without the need for maintaining a huge database of availability at all future times, of all the path resources.

Abstract: The present invention provides a method for enabling Segment Routing in a multi-domain network comprising a client network domain and a server network domain, where the client network domain is a packet network domain and the server network domain is a connected-oriented network domain. The method comprises assigning a network segment identifier to each of one or more potential paths through the server network domain between a pair of overlay network nodes in the client network domain, wherein the one or more potential paths are not pre-configured and the or each network segment identifier is suitable for inclusion in one or more data packets to indicate to at least one of the pair of overlay network nodes a preselected network segment routing for the one or more data packets. The present invention further provides a method for routing data packets in the multi-domain network.

Abstract: The present invention relates to configuring the quality of service in a label switched network. In particular, the invention relates to configuring quality of service for the return path of a bi-directional label switched path in a label switched network. The invention provides a method of configuring quality of service for a return path of a bi-directional label switched path within a network, the bi-directional label switched path having a forward path and a return path. A label information context for a quality of service configuration of the return path of a label switched path is configured separately from a quality of service configuration for the forward path. Path set up messages are formed containing a return path quality of service object indicating the quality of service configuration for the return path separately from a quality of service configuration for the forward path.

Abstract: A method (100) of end-to-end path computation across a plurality of domains (20) in a communication network comprises receiving (101) a request for a path across the plurality of domains. The method comprises computing (110) in a network control entity (50) the end-to-end path across the plurality of domains as part of a hierarchical path computation. Computing the end-to-end path comprises determining if a stored path corresponding to at least a part of the end-to-end path matches one or more criteria of the end-to-end path, and if so, using the stored path for the end-to-end path computation. The method further comprises transmitting (120) information indicating at least part of the stored path to a domain control entity (30) configured to control a said one of the plurality of domains involved in the end-to-end path.

Abstract: A path computation method involves receiving (200) a request for computation of a new path in the network, the request indicating a future time interval when the path is desired. Subsequently a future network status is generated (210, 212, 214), having a representation of availability of path resources at the future time interval, based on selected paths already reserved at that future time interval. Then there is a step of computing (220) which of the path resources to select for the new path according to the future network status. By generating this future network status when the future time interval is known, it can be generated in respect of a limited time interval rather than covering all possible future reservable times. Thus the benefits of time aware path computation can be achieved without the need for maintaining a huge database of availability at all future times, of all the path resources.

Abstract: A method for routing packet traffic through a network comprising a plurality of network nodes supporting RSVP-TE protocol and Segment Routing protocol. Each of the two protocols is associated with a separate set of labels, the method comprises calculating (202) a path through the network; checking support (204) for both protocols at nodes along the calculated path and encoding (206) the calculated path as a set of Adjacency Segment Identifiers. The method also comprises optimising (208) a label stack of the calculated path by substituting more than one adjacency SIDs with a node SID if a partial path identified by the substituted adjacency SIDs equals a shortest path. If all nodes along the calculated path support label stack depth equal to or deeper than the optimised label stack (210) then segment routing is used to set up the path.