Abstract: In one embodiment, a plurality of network interfaces of a network device that are configured to communicate with other network devices in a first computer network are identified as network-to-network interfaces (NNIs). Also, one or more network interfaces of the network device that are configured to provide access to the first computer network to user devices are identified as user-to-network interfaces (UNIs). One or more NNIs of the plurality of NNIs are selected to forward traffic from the network device to an aggregation device of the first network that couples the first computer network to a second computer network. Also, one or more NNIs of the plurality of NNIs that have not been selected to forward traffic from the device to the aggregation device are designated as network-to-network interface alternates (NNI-ALTs). The one or more NNI-ALTs are treated as UNIs for user data traffic forwarding decisions.

Abstract: In one embodiment, a plurality of network interfaces of a network device that are configured to communicate with other network devices in a first computer network are identified as network-to-network interfaces (NNIs). Also, one or more network interfaces of the network device that are configured to provide access to the first computer network to user devices are identified as user-to-network interfaces (UNIs). One or more NNIs of the plurality of NNIs are selected to forward traffic from the network device to an aggregation device of the first network that couples the first computer network to a io second computer network. Also, one or more NNIs of the plurality of NNIs that have not been selected to forward traffic from the device to the aggregation device are designated as network-to-network interface alternates (NNI-ALTs). The one or more NNI-ALTs are treated as UNIs for user data traffic forwarding decisions.

Abstract: In one embodiment, a network device may have its network interfaces identified as either network-to-network interfaces (NNIs) configured to communicate with other network devices in a first computer network, or user-to-network interfaces (UNIs) configured to provide service to the first computer network for user devices. Based on determining at least one NNI for forwarding upstream traffic to an aggregation device of the first network that connects the first network to a second network, any NNI that is not used for forwarding upstream traffic is deemed a novel “NNI alternate” (NNI-ALT). The forwarding of traffic at the network device may be controlled to provide user isolation between network devices by denying traffic forwarding between UNIs and NNI-ALTs as well as between NNI-ALTs and NNI-ALTs, while permitting traffic forwarding between NNIs and NNI-ALTs.

Abstract: In one embodiment, a network device may have its network interfaces identified as either network-to-network interfaces (NNIs) configured to communicate with other network devices in a first computer network, or user-to-network interfaces (UNIs) configured to provide service to the first computer network for user devices. Based on determining at least one NNI for forwarding upstream traffic to an aggregation device of the first network that connects the first network to a second network, any NNI that is not used for forwarding upstream traffic is deemed a novel “NNI alternate” (NNI-ALT). The forwarding of traffic at the network device may be controlled to provide user isolation between network devices by denying traffic forwarding between UNIs and NNI-ALTs as well as between NNI-ALTs and NNI-ALTs, while permitting traffic forwarding between NNIs and NNI-ALTs.