  Nature has always been an inspiration to researchers with its diversity and
robustness of its systems, and Artificial Immune Systems are one of them. Many
algorithms were inspired by ongoing discoveries of biological immune systems
techniques and approaches. One of the basic and most common approach is the
Negative Selection Approach, which is simple and easy to implement. It was
applied in many fields, but mostly in anomaly detection for the similarity of
its basic idea. In this paper, a review is given on the application of negative
selection approach in network security, specifically the intrusion detection
system. As the work in this field is limited, we need to understand what the
challenges of this approach are. Recommendations are given by the end of the
paper for future work.
