8. A dual hash apparatus for use with a pattern search engine, comprising: said pattern search engine comprising a programmable state machine comprising a balanced routing table search (BaRT)-based finite state machine (BFSM), said BFSM being implemented in hardware or a combination of hardware and software; an initial rule bank, a default rule bank and a transition rule bank, each said rule having a test portion to determine if there is a match to a current rule, and a result portion which defines the next state targeted by said rule; said default rule bank operative to store default rules and dual hash rules that apply to a pattern context search; a said transition rule bank operative to store transition rules that apply to a pattern context search; and hash circuits coupled to said default rule bank and said transition rule bank, said hash circuit operative to determine a winning rule by prioritizing between a dual hash rule read from a default rule bank and a transition rule read from a transition rule bank; said dual hash being used: (1) when input values covered by said transition rules are a super-set of the input values covered by said default rules; (2) the previous coverage can also be enforced by adding missing input values of one or more said default rules to a given state; and for anchored matching after a first character, in which event, said default rules are used only for a first character, unless said default rules are used to generate LRP commands; said hash circuits being used for any state for which the input values covered by said transition rules are a super-set of the input values covered by said default rules; the previous coverage can also be enforced by adding the uncovered input values of one or more default rules to a given state; and can always be used for anchored matching after the first character, in anchored matching, the default rules are restricted to the use for the first character only, unless they are used to generate LRP commands; and during a rule check and selection in said dual hash state, a cycle on which said default side of said search engine is running in a dual hash mode, there is no default rule checking and all said rules from said rules in said default bank and said transition bank are considered transition rules and said rules on said transition side have higher priority than the rules on said default side, whereupon, in the event there is no match on either one of said rules, said search engine reverts to said initial state; in said dual hash state, a dual hash table ID and a valid indication indicating a valid bit of the dual hash are maintained in a state block as part of a search state; where multiple rules are present in a given rule line and where each said rule refers to a different dual hash next state, then dual hash rules for said different next states are organized by being mapped together on a single line within said default bank or being separately mapped on multiple lines within said default bank, wherein for each of said mapped in a single-line manner or said multi-line manner, a shared command field comprises all required information for performing independent hash lookups for said rules.
8. A dual hash apparatus for use with a pattern search engine, comprising: said pattern search engine comprising a programmable state machine comprising a balanced routing table search (BaRT)-based finite state machine (BFSM), said BFSM being implemented in hardware or a combination of hardware and software; an initial rule bank, a default rule bank and a transition rule bank, each said rule having a test portion to determine if there is a match to a current rule, and a result portion which defines the next state targeted by said rule; said default rule bank operative to store default rules and dual hash rules that apply to a pattern context search; a said transition rule bank operative to store transition rules that apply to a pattern context search; and hash circuits coupled to said default rule bank and said transition rule bank, said hash circuit operative to determine a winning rule by prioritizing between a dual hash rule read from a default rule bank and a transition rule read from a transition rule bank; said dual hash being used: (1) when input values covered by said transition rules are a super-set of the input values covered by said default rules; (2) the previous coverage can also be enforced by adding missing input values of one or more said default rules to a given state; and for anchored matching after a first character, in which event, said default rules are used only for a first character, unless said default rules are used to generate LRP commands; said hash circuits being used for any state for which the input values covered by said transition rules are a super-set of the input values covered by said default rules; the previous coverage can also be enforced by adding the uncovered input values of one or more default rules to a given state; and can always be used for anchored matching after the first character, in anchored matching, the default rules are restricted to the use for the first character only, unless they are used to generate LRP commands; and during a rule check and selection in said dual hash state, a cycle on which said default side of said search engine is running in a dual hash mode, there is no default rule checking and all said rules from said rules in said default bank and said transition bank are considered transition rules and said rules on said transition side have higher priority than the rules on said default side, whereupon, in the event there is no match on either one of said rules, said search engine reverts to said initial state; in said dual hash state, a dual hash table ID and a valid indication indicating a valid bit of the dual hash are maintained in a state block as part of a search state; where multiple rules are present in a given rule line and where each said rule refers to a different dual hash next state, then dual hash rules for said different next states are organized by being mapped together on a single line within said default bank or being separately mapped on multiple lines within said default bank, wherein for each of said mapped in a single-line manner or said multi-line manner, a shared command field comprises all required information for performing independent hash lookups for said rules. 12. The apparatus according to claim 8 , wherein a dual hash lookup is utilized for anchored matching.