A New Artificial Immune System for the Detection of Abnormal Behaviour

We propose in this paper a new Artificial Immune System (AIS) named NK system, for the detection of abnormal behaviour with an unsupervised approach. Its originality resides in the unsupervised detection based on the mechanism of NK cell (Natural Killer cell) contrary to the existing AIS that use supervised approaches based on the mechanisms of the T and B cells. The NK cells develop the capacity to recognize the molecules of self-MHC through a unique class of receptors that can inhibit or activate its natural mechanism of the antigens elimination. In this paper, the NK system is applied to the detection of fraud in mobile phone. The experimental results axe very satisfactory instead of the very weak proportion of the fraudulent operations in our sample.