Abstract- The rapid growth in the usage of the internet had led to many serious security issues in the network. The intrusion detection system (IDS) is one of the sophisticated defensive systems used to detect the malicious activities happening in the network services across the world.Hence, more advanced IDS are been developed in past few years. To improve the performance of the IDS, the system has to be trained effectively to increase the efficiency and decrease the false alarm rate. To train the system the attributes selection plays the major role.This paper evaluates and compares the performance of the intrusion detection systems for different feature reduction techniques in high speed networks.