摘要:
In one embodiment, a packet switching device assigns a same particular packet switching label to each particular route of a plurality of particular routes having the same one or more best paths, wherein the plurality of particular routes includes routes from at least two different forwarding groups. A forwarding group is defined as a specific route, one or more routes associated with a same customer edge router, or one or more routes associated with a single virtual routing and forwarding domain (VRF). The packet switching device advertises to other packet switching device(s) to add this same particular label to packets having one of the plurality of particular routes, which they do. The packet switching device then packet switches packets based on the particular label received in a label field in a header of these packets.
摘要:
In one embodiment, single-homing and active-active multi-homing is provided in a Virtual Private LAN Service (VPLS). A customer edge node actively communicates frames of a same Virtual Private Network (VPN) instance with two or more VPLS nodes of a VPLS network. The VPLS nodes are configured to appropriately forward frames throughout the VPLS network: without looping of a frame sent by the same external node back to the same external node, without flooding multiple copies of a frame to the same external node, and while performing learning of addresses in forwarding tables of said VPLS nodes such that said forwarding tables of said VPLS nodes converge despite frames of the same LAN service being received by said at least two of said VPLS nodes from the same external node.
摘要:
In one example embodiment, a system and method is illustrated that includes receiving connectivity data for at least one network device, the connectivity data describing a connection to the at least one network device within an area. The system and method further includes processing the connectivity data to obtain a routing update for distribution to another network device outside the area. Additionally, the system and method includes a routing summary in the routing update, the routing summary including an address prefix. Further, the system and method includes reachability information in the routing update, the reachability information including an address for the at least one network device.
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 virtual private network (VPN) is formed with a pair of autonomous systems (ASes) connected by each having at least two autonomous system border routers (ASBRs) connected to the corresponding ASBRs at the other AS, referred to as an Option B VPN-IPv4 network. Route reflectors (RRs) only reflect the best Border Gateway Protocol (BGP) paths, providing no backup BGP paths for fast convergence. Advantageously, an automatic route distinguisher (RD) rewrite component at the ASBRs creates unique prefixes and advertises the original RD as transitive attribute in an update message to external AS peers. Each RD gets mapped to another unique prefix at the ASBR and also that two ASBRs will create different unique prefixes. Thus, the route reflector sees different prefixes and reflects all of them. The ingress provider edge (PE) router can import the prefixes and correctly obtain the alternate paths for fast convergence.
摘要:
Disclosed are, inter alia, methods, apparatus, computer-readable media, mechanisms, and means for deterministically determining MPLS labels as functions of addresses of Forwarding Equivalence Classes (FECs), and using these determined labels in the forwarding of packets. By each packet switching device in a network deterministically determining the same MPLS label to use for each FEC, each packet switching device knows what label will be used by the other packet switching devices, without running Label Distribution Protocol (LDP) or another label publishing protocol. Additionally, this knowledge extends to all packet switching devices in a network, not merely neighboring packet switching devices, which allows a packet switching device to specify a stack of labels to define a desired path through the network for explicit path routing and/or fast rerouting of traffic without having to previously establish a tunnel or path using Resource Reservation Protocol (RSVP), for example.
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:
In one embodiment, a device of a particular non-backbone routing domain in a computer network determines whether each of one or more routes is reachable within the particular non-backbone domain. The device may then generate a filtered set of label mappings having only those of the one or more routes reachable within the particular non-backbone domain. Accordingly, the device may advertise label mappings only of the filtered set to one or more neighboring devices.