Scalable Lookahead Regular Expression Detection System for Deep Packet Inspection

—Regular expressions (RegExes) are widely used, yet their inherent complexity often limits the total number of RegExes that can be detected using a single chip for a reasonable throughput. This limit on the number of RegExes impairs the scalability of today’s RegEx detection systems. The scalability of existing schemes is generally limited by the traditional detection paradigm based on per-character-state processing and state transition detection. The main focus of existing schemes is on optimizing the number of states and the required transitions, but not on optimizing the suboptimal character-based detection method. Furthermore, the potential benefits of allowing out-of-sequence detection, instead of detecting components of a RegEx in the order of appearance, have not been explored. Lastly, the existing schemes do not provide ways to adapt to the evolving RegExes. In this paper, we propose Lookahead Finite Automata (LaFA) to perform scalable RegEx detection. LaFA requires less m...

• Type: Journal
• Year: 2012
• Where: TON
• Authors: Masanori Bando, N. Sertac Artan, H. Jonathan Chao
• Keywords: Detection Modules, Lafa, Programmable Gate Array, Programming Languages, TON 2012