Hardware Accelerator for Subgraph Isomorphism Problems

Many applications can be m o deled a s s u b graph iso-morphism problems, which are g e n e r ally NP-complete. This paper presents an algorithm that is suited for hardware implementation. The prototype a c celerator that operates at 16.5 MHz on a Lucent ORCA 2C15A FPGA outperforms the software implementation of Ullmann's algorithm on a 400 MHz Pentium II by 10 times in the best case. 1 Subgraph Isomorphism Many applications, including scene analysis and chemical structural formula databases, are modeled as subgraph isomorphism problems. However, subgraph isomorphism is generally NP-complete [1] and dicult to compute within a reasonable time. First, let us dene the problem.