Patent ID: 6813273
Filing Date: 2004-11-02
Classification: H04L

Abstract:
A method for determining if it is necessary to perform a search for a specified address in an address lookup table (LUT) containing a plurality of addresses, said method comprising:providing at least one ordered list of address existence fields associated with lookup addresses obtained from at least one portion of said plurality of addresses; indexing into said at least one ordered list to access at least one address existence field associated with a corresponding portion of said specified address; and checking said at least one address existence field to determine if a search of said specified address in said address LUT is necessary; wherein said providing at least one ordered list includes: determining a smallest and a largest lookup address of lookup addresses that define limits of a range of lookup addresses; allocating address existence fields for a predetermined number of said lookup addresses in said range; and initializing address existence fields corresponding to said range of lookup addresses to indicate existence of corresponding addresses in said address LUT, wherein indexing into said at least one ordered list includes indexing into said at least one ordered list if said specified address has a corresponding address portion in said range.