摘要:
Hiding a service node in a network from a network topology is provided. In one embodiment, for example, an apparatus for hiding a service node in a network from a network topology, the apparatus comprising: a network interface; a processor; and one or more stored sequences of instructions which, when executed by the processor, cause the processor to perform: discovering a service node in a data network in accordance with a link-state protocol wherein the service node provides a network topology dependent service other than packet forwarding; establishing a link-state adjacency with the service node and one or more packet forwarding nodes in accordance with the link-state protocol; receiving a link-state advertisement; in response to identifying the link-state advertisement as an originating link-state advertisement sent from the service node, suppressing flooding of the received link-state advertisement to the one or more packet forwarding nodes.
摘要:
Hiding a service node in a network from a network topology is provided. In one embodiment, for example, an apparatus for hiding a service node in a network from a network topology, the apparatus comprising: a network interface; a processor; and one or more stored sequences of instructions which, when executed by the processor, cause the processor to perform: discovering a service node in a data network in accordance with a link-state protocol wherein the service node provides a network topology dependent service other than packet forwarding; establishing a link-state adjacency with the service node and one or more packet forwarding nodes in accordance with the link-state protocol; receiving a link-state advertisement; in response to identifying the link-state advertisement as an originating link-state advertisement sent from the service node, suppressing flooding of the received link-state advertisement to the one or more packet forwarding nodes.
摘要:
A method and apparatus are disclosed for performing a shortest path first network routing path determination in a data communications network based in part on information about links that are associated as shared risk link groups. Micro-loops are avoided in computing shortest path first trees by considering whether links are within shared risk link groups. In a first approach, for each link state packet in a link state database, listed adjacencies are removed if the link between the node originating the LSP and the reported adjacency belongs to a shared risk link group for which one component (local link) is known as down, and a shortest path first computation is then performed. In a second approach, during the SPT computation and after having added a first node to a path, each neighboring node is added to a tentative tree if and only if, a link between the first node and the neighboring node does not belong to a shared risk link group for which one component (local link) is known as down.
摘要:
In one embodiment, a router in a routing domain exchanges routing information with one or more other routers located external to the routing domain using an exterior gateway protocol (EGP). The router exchanges routing information with one or more other routers located internal to the routing domain using an interior gateway protocol (IGP). The router detects a route to be advertised by the IGP is also used as a next-hop attribute of a route advertised by the EGP. In response, the router tags the route advertised by the IGP as an important route for convergence to indicate that the tagged route is to be processed before other routes that have not been tagged during convergence processing. The tagged route is advertised within the routing domain using the IGP.
摘要:
In one embodiment, an edge device in a first routing domain is configured to communicate with a second routing domain via a data link. The edge device receives a data packet containing a destination address that is reachable via the second routing domain and an indication that the data packet is a protected packet that was previously rerouted from another edge device in the first routing domain via a Multi-Protocol Label Switching (MPLS) Fast Reroute (FRR) backup path. The edge device determines if communication with the second routing domain is still available via the data link, and if so, removes the indication that the data packet is a protected packet and forwards the data packet to the second routing domain, and, if not, drops the data packet to prevent the data packet from being rerouted a second time in the first routing domain on another MPLS FRR backup path.
摘要:
In one embodiment, a loss of communication is detected between a first edge device of a computer network and a neighboring routing domain. A data packet is received at the first edge device, where the received data packet contains a destination address that is reachable via the neighboring routing domain. A determination is made whether a service label is located in a Multi-Protocol Label Switching (MPLS) label stack included in the received data packet. A service label in the MPLS label stack indicates that the received data packet was previously rerouted in accordance with fast reroute (FRR) operations. In response to a determination that the received data packet does not include a service label in the MPLS label stack, the received data packet is rerouted to a second edge device of the computer network for forwarding to the neighboring routing domain.
摘要:
A method of constructing a backup path in an autonomous system (AS) for failure of an inter-AS link is described. The method comprises identifying an alternate inter-AS path and constructing a tunnel to an end point on the alternate path.
摘要:
A method and system for protecting valuable resources within an autonomous system network. Address prefixes within the system are designated as valuable and a flag bit is associated with the address within routing tables of routers of the network. Interfaces to border routers are identified and when packets are received at those interfaces, the packets are flagged with a flag or tag bit. The destination address of the received packet is compared to the flag bit associated with the valuable resource prefix, and if the packet is directed to that resource the packet is dropped and/or logged, but the packet is not forwarded to that resource. In specific cases an interface from an external source may be configured to not create the flag or tag bit, wherein that packet will be delivered to the destination prefix of the packet.
摘要:
In one embodiment, a trigger to add a leaf node to a multicast group of a computer network is detected, and the leaf node may determine a root node of the multicast group to request a path between a tunnel tree and the leaf node of the multicast group. In response to the multicast group having an existing tree, a reply is received from the root node with a computed path to add the leaf node to the tree at a selected node of the tree. The leaf node may then be added to the multicast group tunnel tree over the computed path at the selected node.
摘要:
In one embodiment, a node identifies a plurality of equal cost best paths to a destination, the best paths having one or more associated links. The node receives dynamic link utilization information for the associated links, and determines an amount of traffic to the destination to forward over each of the equal cost best paths, the amount being dynamically dependent upon the dynamic link utilization of the associated links for each equal cost best path.