A Novel Fast Negative Selection Algorithm Enhanced by State Graphs

Negative Selection Algorithm is widely applied in Artificial Immune Systems, but it is not fast enough when there are mass data need to be processed. Multi-pattern matching algorithms are able to locate all occurrences of multi-patterns in an input string by just one scan operation. Inspired by the multi-pattern matching algorithm proposed by Aho and Corasick in 1975 [1], a novel fast negative selection algorithm is proposed for the “r-contiguous-bits” matching rule in this paper. The algorithm constructs a self state graph and a detector state graph according to the self set and the detector set respectively, and processes input strings using partial matching algorithm based on the state graph. The time complexity of this algorithm when processing an input string of length l is O(l). Experiments are carried out to make comparisons on the time and space costs between this new algorithm and the traditional negative selection algorithm.