Abstract: In an embodiment, a method of signaling status at a routing device is provided. In this method, the routing device establishes an inter-chassis control plane channel session with a remote routing device. Here, the routing device and the remote routing device are linked to a multi-homed routing device. The routing device then synchronizes with the remote routing device by way of the inter-chassis control plane channel session to identify a state of a link from the routing device to the multi-homed routing device. The state of the link is thereafter advertised by way of Border Gateway Protocol (BGP). Additionally, a method of discovering inter-chassis communication peers via BGP between the first and remote routing devices is provided.

Abstract: In an embodiment, a method of signaling status at a routing device is provided. In this method, the routing device establishes an inter-chassis control plane channel session with a remote routing device. Here, the routing device and the remote routing device are linked to a multi-homed routing device. The routing device then synchronizes with the remote routing device by way of the inter-chassis control plane channel session to identify a state of a link from the routing device to the multi-homed routing device. The state of the link is thereafter advertised by way of Border Gateway Protocol (BGP). Additionally, a method of discovering inter-chassis communication peers via BGP between the first and remote routing devices is provided.

Abstract: A method is provided for generating a backup route. Here, a route and a route distinguisher type associated with the route are received and a backup route is generated based on attributes of the route. A particular backup route distinguisher type that is associated with the route distinguisher type is assigned to the backup route. The backup route with the backup route distinguisher type are then advertised. Another method is provided that identifies the backup route. When the route and its route distinguisher type are received from the advertisement, an identification is made as to whether the route distinguisher type is assigned to a backup route. The route may then be designated as a backup route based on the identification.

Abstract: 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.

Abstract: In an embodiment, a method of signaling status at a routing device is provided. In this method, the routing device establishes an inter-chassis control plane channel session with a remote routing device. Here, the routing device and the remote routing device are linked to a multi-homed routing device. The routing device then synchronizes with the remote routing device by way of the inter-chassis control plane channel session to identify a state of a link from the routing device to the multi-homed routing device. The state of the link is thereafter advertised by way of Border Gateway Protocol (BGP). Additionally, a method of discovering inter-chassis communication peers via BGP between the first and remote routing devices is provided.

Abstract: A method is provided for generating a backup route. Here, a route and a route distinguisher type associated with the route are received and a backup route is generated based on attributes of the route. A particular backup route distinguisher type that is associated with the route distinguisher type is assigned to the backup route. The backup route with the backup route distinguisher type are then advertised. Another method is provided that identifies the backup route. When the route and its route distinguisher type are received from the advertisement, an identification is made as to whether the route distinguisher type is assigned to a backup route. The route may then be designated as a backup route based on the identification.

Abstract: A method of selecting routing tables to include in a network line card consists of determining dependencies of local routes on remote routes using a reference count on prefixes, and selectively downloading remote routes when resolution of a route has a dependency on a remote route. In one embodiment, only remote routes that are needed to forward traffic are downloaded to a network line card.

Abstract: 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.

Abstract: A method of selecting routing tables to include in a network line card consists of determining dependencies of local routes on remote routes using a reference count on prefixes, and selectively downloading remote routes when resolution of a route has a dependency on a remote route. In one embodiment, only remote routes that are needed to forward traffic are downloaded to a network line card.