Patent ID: 6438129
Filing Date: 2002-08-20
Classification: H04L

Abstract:
A method of performing source address look-ups in a network switch which receives frames including source addresses and destination addresses and which includes a forwarding database containing entries each comprising a source address read from an incoming packet and a number identifying a port by which that frame has been received, the method comprising:(a) performing a destination address look-up on the entries in the database for an incoming frame to determine whether the database contains an entry including a source address corresponding to the destination address of the received packet; (b) performing a source address look-up through the entries in the database for the source address contained within a received frame; (c) maintaining a token count; (d) incrementing the token count from time to time; (e) decrementing the token count when a source address look-up in the forwarding database is performed; and (f) inhibiting source address look-ups when the token count is reduced to a datum.