PARTITIONING OF SHARED RESOURCES AMONG CLOSED USER GROUPS IN A NETWORK ACCESS DEVICE

摘要

A network access device includes a cell buffer memory (54) and segmentation and reassembly (SAR) logic (40) between multiple local area network (LAN) interface logic blocks (33, 36) and logic (56) interfacing with a cell-based network such as ATM. The cell buffer memory can be programmably partitioned into distinct buffer regions, each being associated with a respective LAN and with a respective set of virtual connections on the cell-based network. The SAR logic segments received frames into groups of cells, stores each group of cells into the buffer region associated with the respective LAN, and transfers the groups of cells from each buffer region to the all-based-network interface logic via the associated virtual connections. The SAR logic and the cell memory are shared among multiple LAN bridges implemented by the LAN interface logic blocks and the cell-based-network interface logic, while traffic from the different bridges is kept separate. The SAR logic also manages the network bandwith assigned to the different bridges separately, so that traffic from one bridge generally does not affect another bridge's use of its allocated bandwidth.