Fast Pattern Matching Using Dynamically Partitioned AC-DFAs

Pattern matching is a critical component of deep packet inspection (DPI). To provide fast matching speed, deterministic finite automata constructed with the Aho-Corasic algorithm (AC-DFA) has been widely used. The matching speed of an AC-DFA is highly affected by the memory size used to store the DFA. In this paper, we propose a fast pattern matching algorithm using partitioned AC-DFAs. Most pattern matching algorithms using AC-DFAs partition an AC-DFA statically. Our proposed algorithm, however, dynamically partitions an AC-DFA according to inspected packet payloads. Simulation results show that our proposed algorithm achieves a higher matching speed (from 15% to 176%) than other two pattern matching algorithms that use partitioned AC-DFAs.