A Survey on Regular Expression Matching for Deep Packet Inspection: Applications

Deep packet inspection (DPI) is widely used in content-aware network applications such as network intrusion detection systems, traffic billing, load balancing, and government surveillance. Pattern matching is a core and critical step in DPI, which checks the payload of each packet for known signatures (patterns) in order to identify packets with certain characteristics (e.g., malicious packets that carry viruses or worms). Regular expression is the major tool for signature description due to its