1. A method for evaluating contents of a message, comprising: characterizing a message segment, wherein the message segment further comprises a packet in a packet-switched network; scanning the message segment to define a stream of tokens associated with the message segment; associating the message segment with a meta session through the stream of tokens, wherein the meta session is made persistent across message transactions and different HTTP sessions by storing data generated by the meta session on a persistent storage medium; parsing the token stream to extract substructures according to a grammar; determining rules associated with the tokens, the rules when executed defining actions for intrusion detection and prevention; executing the actions associated with the message segment; and queuing the message segment for transmission to a destination, wherein each of the operations in the method is executed by an integrated circuit.
5. The method of claim 1 , wherein the method operation of determining rules associated with the tokens includes, defining an object oriented scheme to associate the message segment with at least one of the rules.