The term filter bridge can be used for a static bridge, for learning bridges or for routing bridges such as brouters. All these bridges have filter functionality in the sense of a more or less refined load separation between subnets.
A filter bridge can filter out data packets according to predefined criteria by setting a packet filter, thereby enabling logical separation between two or more LAN segments. The filter functions can be set automatically (Learning Bridge) or manually. Remote brid ges and multiway bridges are usually self-learning and implement path selection functions.
One criterion for the transmission behaviour of filter bridges is the filtering rate. It indicates how many data packets a filter bridge can receive and process. If the maximum number of data packets is exceeded, the excess data packets sent cannot be accepted by the filter bridge.