Abstract: A system which uses per-port last source address registers, which are part of the repeater function, for making filtering/forwarding decisions, which are part of the bridging function. The system includes a single repeater collision domain divided into segments, one or more transceivers for each segment, a master management device/bridge for the first segment, and one or more slave management devices for the remaining segments. A local signal which allows the forwarding/filtering decision to be distributed is attached to the master management device and all slave management devices. A remote bridge interface is attached to the master management device. A management interface for each management device, either master or slave, is used to attach each management device to its respective transceiver for the ports which controlled by the management device.

Abstract: A method and apparatus for implementing a two-port Ethernet bridge using a semaphoring technique. The Ethernet bridge includes two MAC devices, a bus, a memory and a semaphoring scheme. The controllers include a first address which is used for indicating receipt of the packet and a second address which is used for indicating the transmission of the packet from the memory and for clearing of the memory location of the packet for further use. The receiving media access controller receives a data packet on a first port and the transmitting media access controller transmits the packet from the memory to a second port associated with the address of the intended user designated by the packet. The memory includes a dual-ring structure, with one ring used for receive traffic and the other ring used for transmit traffic. The MACs also include programmability for designating the type of packets that may be received.

Abstract: A configurable network interface controller that provides for the automatic retransmission of collided Ethernet frames from a local RAM while observing two modes of operation: (1) retransmission of as much of the frame as possible without violating latency requirements and (2) first guaranteeing the safe retransmission of the first 64 bytes and then returning to observation of the latency requirements.