Patent ID: 6850521

Claim:
A network switch for switching packets from a source to a destination, said network switch comprising: a source port for receiving an incoming packet from a source; a destination port which contains a path to a destination for the packet; a filter unit for constructing and applying a filter to selected fields of the incoming packet, said filter unit comprising filtering logic for selecting desired fields of the incoming packet and obtaining selected field information therefrom, said filtering logic constructing a field value based upon the selected fields, wherein the filtering logic applies a plurality stored field masks on the field value to create a filter value; said switch further comprising a rules table which contains a plurality of rules therein, wherein the filtering logic performs a lookup of the rules table in order to determine actions which must be taken; and wherein the filtering logic is configured to concatenate the filter value with at least one predetermined packet field to create a search key and the lookup of the rules table is made using the search key as a key to the rules table.