Abstract: A method and system for extending a plurality of sub-interfaces of a router port of a wide area network access device to a plurality of user networks using a transport network is provided. The transport network comprises a plurality of network nodes coupled together by one or more data communication paths wherein at least one of the network nodes comprises an access device. The access device includes a plurality of router port extension functional units wherein each router port extension functional unit is coupled to one of the user networks. Each router port extension functional unit comprises a virtual channel agent and a LAN agent. Each router port extension functional units has an associated virtual port, and all of the virtual ports are multiplexed to a single LAN communication port.

Abstract: A buffer storage system is provided for storing groupings of data of varying size. The buffer storage system comprises a buffer storage section and a buffer management section. The buffer storage section has a first buffer subsection and a second buffer subsection. The first buffer subsection includes a plurality of buffer units of a first buffer unit size. The second buffer subsection includes a plurality of buffer units of a second buffer unit size wherein the second buffer unit size is larger than the first buffer unit size. The buffer management section is operable to determine the size of an incoming data grouping and to direct the incoming data grouping to one of the buffer subsections based on the size of the data grouping.

Abstract: A system and method for transporting data packets in a ring network includes a plurality of network nodes having a protection switching agent and at least one fast downstream path circuit that provides a low-latency packet cut-through function for forwarding packets from an upstream node to a downstream node. The network nodes include three interfaces, two interfaces for coupling the network node to other network nodes in the ring network, and a third interface for coupling the network node to a local node. A plurality of virtual paths are provided between a data packet gateway, such as an Internet gateway, and the local nodes that are coupled to the network nodes of the ring network. A virtual channel identifier is embedded within data packets transported on the network so that the protection switching agent in each network node can determine whether to route received data packets to the local node, or to the low-latency cut-through downstream path circuit.

Abstract: A system and method for path protection switching in ring networks is provided in which the path protection switch occurs at the transmitter node that initiated a particular virtual channel of data packets onto the ring network. A failure in one of the data communication-paths of the ring network is detected by the network nodes on either side of the failure. These network nodes then initiate a wrap mechanism that embeds a special feedback wrap indicator flag into packets received at the two nodes, and then wraps (or transmits back) these packets (with the feedback indicator) in the opposite direction towards the transmitter node that initiated the packets onto the ring. Each transmitter node detects whether received packets are associated with virtual channels that it initiated onto the ring and if so detected, then determine whether the feedback indicator flag is set.

Abstract: A buffer storage system is provided for storing groupings of data of varying size. The buffer storage system comprises a buffer storage section and a buffer management section. The buffer storage section has a first buffer subsection and a second buffer subsection. The first buffer subsection includes a plurality of buffer units of a first buffer unit size. The second buffer subsection includes a plurality of buffer units of a second buffer unit size wherein the second buffer unit size is larger than the first buffer unit size. The buffer management section is operable to determine the size of an incoming data grouping and to direct the incoming data grouping to one of the buffer subsections based on the size of the data grouping.

Abstract: A method and system for extending a plurality of sub-interfaces of a router port of a wide area network access device to a plurality of user networks using a transport network is provided. The transport network comprises a plurality of network nodes coupled together by one or more data communication paths wherein at least one of the network nodes comprises an access device. The access device includes a plurality of router port extension functional units wherein each router port extension functional unit is coupled to one of the user networks. Each router port extension functional unit comprises a virtual channel agent and a LAN agent. Each router port extension functional units has an associated virtual port, and all of the virtual ports are multiplexed to a single LAN communication port.