Conclusion
This paper elucidates the advantages of lazy learning in IDS. Lazy learning improves the efficiency of the NIDS by eliminating pre-fetching of overheads that are inherent in eager learning algorithms popularly in use today. Further an improvement of the k-nearest neighbour algorithm has been proposed to reduce the search complexity using a heuristic weight based indexing system. The results of this sufficiently prove thehw-IBk algorithm is a practical and viable solution for intrusion detection in data streams, with great accuracy,more so than other machine learning algorithms currently deployed. Additionally, the IBk algorithm has been compared to another other lazy learning algorithmLWL in order to compareand contrast their performances on the NSL-KDD network traffic dataset.The time taken to detect intrusions is significantly reduced and it is observed that the number of correctly classified instances of intrusions is relatively higher (~97.59).Thus, with significant increase in the speed of computation, network intrusions can now be detected faster without any loss to accuracy and thus aid in threat identification in real-time network system.