The Network Intrusion Detections System Of Multilayer Pattern Matching

With the appearance of High-speed network of broadband, how to detect the happening of intrusion affairs in the network truly and fleetly is a great problem that the Intrusion detections must face, under the environment of high-speed network.This article mainly focuses on the setting-up of the model of intrusion detections system, the pattern matching algorithms used in intrusion detections and the setting-up of the intrusion pattern base and distribution of patterns. It not merely relates to the performance of the pattern algorithms to improve the efficiency of intrusion detections, still there is a very great relation with the distribution of patterns in the pattern base. The innovative point of the article is the achievement of layered intrusion pattern base. It is mature and perfect to improvement the efficiency of intrusion detection by the way of advancing the efficiency of pattern matching arithmetic at present, so the article finds a new method that is to distribute the intrusion pattern base, the article use the method of PRI, which divide the intrusion pattern base into four different level pattern base, and different pattern base have different level to match. Distribute the intrusion pattern which happened in higher rate into the higher level intrusion pattern base .It use the way of reducing the member of matching pattern in one successful pattern matching to advance the efficiency of intrusion detection. It uses the index to implement the distributing of the pattern base logically, which could avoid the additional cost in time and space while adjusting the pattern base. It implements the dynamic adjusting of pattern base, so the pattern base could be adapted with the change of current intrusion.