An Efficient Regular Expressions Compression Algorithm From a New Perspective

Deep packet inspection plays a increasingly important role in network security devices and applications, which use more regular expressions to depict patterns. DFA engine is usually used as a classical representation for regular expressions to perform pattern matching, because it only need O(1) time to process one input character. However, DFAs of regular expression sets require large amount of memory, which limits the practical application of regular expressions in high-speed networks. Some compression algorithms have been proposed to address this issue in recent literatures.