Abstract: A method and system for detecting a pattern derived from or related to a data signature in data packets is provided. An intrusion detection module accepts a data packet and compares all or portions of the data packet with a set of data patterns. One or more data patterns may be related to, or indicate the existence of, or derived from a virus or other data structure, software code, software program, portions of content of a data packet, a universal resource locater, and/or a traffic classification indicator.