Abstract: A multi-protocol label switching system using multiple cores. In establishing a virtual private network in a MPLS system, more than one core is available. Paths are established over each core separately and weights are assigned to the two routes. Thus, the route which is preferred by manually configuring in advance will be chosen.

Abstract: Methods and apparatus to determine an alternate route in a network are disclosed. An example method disclosed herein to route a data packet to a destination in a network comprises determining multiplicity values for a set of neighbor nodes, a multiplicity value representing a number of times the data packet has been routed to a respective neighbor node in the set of neighbor nodes, and selecting, based on the multiplicity values, a first neighbor node from the set of neighbor nodes to which to send the data packet to route the data packet to the destination.

Abstract: A method and apparatus for providing communication for virtual private networks in networks such as Voice over Internet Protocol (VoIP) and Service over Internet Protocol (SoIP) are disclosed. The present method enables Service Border Routers (SBRs) to perform mapping of VPN routes between two or more autonomous systems based on Virtual Route Forwarding (VRF) tables configured on each Autonomous System (AS). The method configures cross-connect tables in SBRs for coupling one or more VRF tables in one autonomous system with one or more VRF tables in other autonomous systems.

Abstract: In a network comprising a provider edge router coupled to each of a mated pair of core routers in a core network, a system and methodology for rerouting upstream traffic destined for the provider edge router in the event of a link failure between one of the core routers and the provider edge router. By detecting a link failure between a first of the mated pair of core routers and the provider edge router, and directing the upstream traffic destined for the provider edge router to a second of the mated pair of core routers, internal gateway protocol (IGP) reconvergence events are not triggered.

Abstract: Methods and apparatus to utilize route aggregation for exchanging routes in a communication network are disclosed.

Abstract: Methods and apparatus to utilize route parameter sets for exchanging routes in a communication network are disclosed. An example method to exchange routes in a communication network disclosed herein comprises receiving a route comprising a route identifier identifying the route and a plurality of route parameter values characterizing the route, and sending the route identifier and a pointer to forward the route to a recipient in the communication network, the pointer being associated with a route parameter set comprising the plurality of route parameter values.

Abstract: Example scalable multiprotocol label switching (MPLS) based networks, and methods, apparatus and articles of manufacture to implement the same are disclosed. A disclosed example method includes determining at an area border router (ABR) an OSPF metric representing a cost associated with transporting data between a provider edge router (PER) and the ABR within a non-zero OSPF area, replacing at the ABR a first MPLS label included in a BGP message received from the PER with a second MPLS label associated with the PER and assigned by the ABR, replacing at the ABR a next-hop attribute included in the BGP message with a value representing a loopback address of the ABR, updating at the ABR a route cost attribute included in the BGP message to include the OSPF metric, and re-advertising from the ABR the modified BGP message into an OSPF area 0.

Abstract: Certain exemplary embodiments can provide a method, which can comprise, from a central routing device of a plurality of central routing devices, automatically polling each of a plurality of Provider Edge routers with Bidirectional Forwarding Detection protocol messages. The method can comprise automatically determining a suspected failure of a Provider Edge router of the plurality of Provider Edge routers.

Abstract: A method of operating a communication network comprises receiving loopback addresses from a plurality of edge networks at a provider router of a core backbone network, the edge networks and the core backbone network being logically distinct from each other, advertising the loopback addresses to a transport route reflector element, propagating the advertisement of the loopback addresses to other provider routers of the core backbone network using a protocol for communicating between autonomous systems, and using the transport route reflector element to advertise at least one of the loopback addresses to a service route reflector element in one of the plurality of edge networks.

Abstract: A system and method for routing traffic from an ingress provider edge router to an egress provider edge router that eliminates the need to share state information between the ingress provider edge router and a plurality of core routers in a core network. The ingress provider edge router and egress provider edge router are each coupled to at least two core routers among the plurality of core routers in the core network, the ingress provider edge router learning routes with a next hop equal to an IP address of the egress provider edge router through an internal border gateway protocol (iBGP). The ingress provider edge router balances traffic flows on uplinks between the ingress provider edge router and the at least two core routers coupled to the ingress provider edge router without knowledge of network topology in the core network.

Abstract: A backbone network may include first and second border routers and a route reflector. The first border router may provide data connectivity between the backbone network and a first regional network. The first border router may be configured to receive a notification of a change in status of an edge router of the first regional network, and the notification may be received according to a first routing protocol. The first border router may be further configured to redistribute the notification of the change in status of the edge router from the first routing protocol to a second routing protocol with the first and second routing protocols being different. The second border router may provide data connectivity between the backbone network and a second regional network. The route reflector may be coupled between the first and second border routers, and the route reflector may be configured to transfer the redistributed notification from the first border router to the second border router.

Abstract: A backbone network may include first and second border routers and a route reflector. The first border router may provide data connectivity between the backbone network and a first regional network. The first border router may be configured to receive a notification of a change in status of an edge router of the first regional network, and the notification may be received according to a first routing protocol. The first border router may be further configured to redistribute the notification of the change in status of the edge router from the first routing protocol to a second routing protocol with the first and second routing protocols being different. The second border router may provide data connectivity between the backbone network and a second regional network. The route reflector may be coupled between the first and second border routers, and the route reflector may be configured to transfer the redistributed notification from the first border router to the second border router.

Abstract: A multi-protocol label switching system using multiple cores. In establishing a virtual private network in a MPLS system, more than one core is available. Paths are established over each core separately and weights are assigned to the two routes. Thus, the route which is preferred by manually configuring in advance will be chosen.

Abstract: In a network comprising a provider edge router coupled to each of a mated pair of core routers in a core network, a system and methodology for rerouting upstream traffic destined for the provider edge router in the event of a link failure between one of the core routers and the provider edge router. By detecting a link failure between a first of the mated pair of core routers and the provider edge router, and directing the upstream traffic destined for the provider edge router to a second of the mated pair of core routers, internal gateway protocol (IGP) reconvergence events are not triggered.

Abstract: A system and method for routing traffic from an ingress provider edge router to an egress provider edge router that eliminates the need to share state information between the ingress provider edge router and a plurality of core routers in a core network. The ingress provider edge router and egress provider edge router are each coupled to at least two core routers among the plurality of core routers in the core network, the ingress provider edge router learning routes with a next hop equal to an IP address of the egress provider edge router through an internal border gateway protocol (iBGP). The ingress provider edge router balances traffic flows on uplinks between the ingress provider edge router and the at least two core routers coupled to the ingress provider edge router without knowledge of network topology in the core network.

Abstract: A multi-protocol label switching system using multiple cores. In establishing a virtual private network in a MPLS system, more than one core is available. Paths are established over each core separately and weights are assigned to the two routes. Thus, the route which is preferred by manually configuring in advance will be chosen.

Abstract: A method for forming a communications network using routers. The first step is analyzing a router location to determine if the router location is VPN resource constrained or interface-constrained. The VPN resource constrained router network comprises at least at least two groups of routers and the same number of customer groups. The next step is connecting the first group of customers and routers, and the second group of customers and routers, using a round robin connectivity methodology and saving information in each router's database. The interface-constrained router network, comprises no more routers than the value [Q*], wherein [Q*] represents the number of routers that can be used by a group of customers so that VPN resources will not be exhausted faster than interface resources for the group of routers, then connecting customers to the group of routers using a round robin connectivity methodology and saving information in each router's database.

Abstract: A system and method for retaining routes in a control plane learned by an inter-domain routing protocol in the event of a connectivity failure between routers. Routers are classified as either route reflectors or originators. A determination is made whether the connectivity failure occurred between a route reflector and an originator, two originators, or two route reflectors. A determination is then made whether to propagate a withdrawal of learned routes based on whether the connectivity failure occurred between a route reflector and an originator, two originators, or two route reflectors. A withdrawal of learned routes is propagated to neighboring routers if the connectivity failure occurred between two originators, or between a route reflector and an originator that is inaccessible via an intra-domain routing protocol.

Abstract: A method and apparatus for providing a flexible virtual forwarding table for packet networks are disclosed. For example, the method receives one or more packets from at least one customer endpoint device, where the one or more packets are destined for a destination node. The method then locates a route for routing the one or more packets by consulting one or more virtual forwarding projection tables, wherein each of the one or more virtual forwarding projection tables contains a subset of the routes that are stored in a virtual route forwarding table. Finally, the method forwards the one or more packets towards said destination node using said route.

Abstract: A method and apparatus for optimally routing a data packet through multiple autonomous networks. A data packet received at an ingress node of a first autonomous network is routed to an egress node of a second autonomous network by selecting an optimal route based on the lowest latency using internal gateway protocol (IGP) routing information of the first and second autonomous networks, which is distributed to nodes of the first and second autonomous network. The data packet is then transmitted along the selected optimal route.