Apparatus for implementing actions based on packet classification and lookup results

Abstract

A method and apparatus are provided for implementing predefined actions based upon packet classification and lookup results in a communications network processor. A plurality of sets of rules is defined. Each rule set includes at least one rule and each rule has a set of masked compares for comparing results of hits and misses of table lookups. Each masked compare set has an associated field for selecting an action. The action defines a set of one or more commands and each command defines a processing operation. One rule set is identified based upon the packet classification result for a received packet. When one of the rules is identified having a match of the masked compares, then the action of associated with the identified rule is selected. Otherwise a default action is provided responsive to no rule of the identified rule set having a match of the masked compares.

1 - 7 . (canceled) 
   
   
       8 . Apparatus for implementing predefined actions based upon packet classification and table lookup results in dataflow assist hardware of a communications network processor, said apparatus comprising:
 a plurality of rule sets, each rule set including at least one rule, each said rule having a set of masked compares for comparing results of hits and misses of table lookups; and each said masked compare having an associated field for selecting an action; said action defining a set of commands; each said command defining a processing operation;   logic for identifying one said rule set based upon the packet classification result;   a masked compares function for identifying one said rule of said identified rule set having a match of said masked compares and a highest priority; said masked compares function includes hardware logic operating in parallel for each said rule of said identified rule set for identifying said match of said masked compares; and   a rule selection function for selecting said action of said identified one said rule.   
   
   
       9 . Apparatus for implementing predefined actions based upon packet classification and table lookup results in a communications network processor as recited in  claim 8  wherein said rule selection function selects a default action responsive to no rule of said identified rule set having a match of said masked compares. 
   
   
       10 . (canceled) 
   
   
       11 . Apparatus for implementing predefined actions based upon packet classification and table lookup results in a communications network processor as recited in  claim 8  wherein said set of masked compares of each said rule includes include a bit mask including a number of bits related to the table lookup results. 
   
   
       12 . Apparatus for implementing predefined actions based upon packet classification and table lookup results in a communications network processor as recited in  claim 11  wherein said bit mask includes a pattern of bit values related to the table lookup results. 
   
   
       13 . Apparatus for implementing predefined actions based upon packet classification and table lookup results in a communications network processor as recited in  claim 12  wherein said pattern of bit values includes a 0 value corresponding to each don't care table lookup result and a 1 value corresponding to a selected table lookup result. 
   
   
       14 . Apparatus for implementing predefined actions based upon packet classification and table lookup results in a communications network processor as recited in  claim 8  wherein said action defining said set of commands include commands for routing, filtering, and decoding processing operations.