An adaptable FPGA-based System for Regular Expression Matching

In many applications string pattern matching is one of the most intensive tasks in terms of computation time and memory accesses. Network Intrusion Detection Systems and DNA Sequence Matching are two examples. Since software solutions are not able to satisfy the performance requirements, specialized hardware architectures are required. In this paper we propose a complete framework for regular expression matching, both in its architecture and compiler. This special-purpose processor is programmed using regular expressions as programming language. With the parallelism exploited in the design it is possible to achieve a throughput greater than one character per clock cycle, requiring O(n) memory space. The VHDL description of the proposed architecture is fully configurable. A design space exploration to find the optimal architecture based on area and performance cost-function is presented.