Self-configuring source-aware bridging for noisy media

Abstract

A source-aware bridging scheme for supporting bridging between a noisy (“unreliable”) network and another, reliable network. Each device connected to the medium of the unreliable network includes a source-aware MAC that maintains a Bridge Proxy Destination Address list (BPDAlist) of all destination addresses that reside on the other network and are reached by a bridge. The BPDAlist information can be learned by the source-aware MAC during a frame receive and/or received during a channel estimation cycle. The list associates destination addresses with the address of the particular bridge through which the destination addresses are accessed. The bridge serves as a proxy with respect to those destination addresses and thus maintains its own list of the destination addresses for which it serves as proxy, or, IAPlist. The IAPlist can be learned, or passed down to the source-aware MAC from a learning bridge process or from the local host to which the device is coupled. The source-aware MAC in each device, including the bridge, supports bridge proxy processing functions. If the device receives a frame intended for transmit and the destination address is a bridged address (that is, is included in the BPDAlist, the bridge proxy processing replaces the destination address with the appropriate bridge address and encapsulates the frame with bridge information that enables the bridge to reconstruct the original frame. If the device is a bridge, the processing replaces the source address with the address of the bridge and updates the IAPlist with the source address. If a frame with bridge information is received from the medium, the bridge proxy processing restores the frame from the bridge information and may use the bridge information to update the BPDAlist.