With the expansion of the openness and pupularization and sharing and interconnection of computer network technology . Network security has become an international problem, every year The aggregate loss that has been caused by the damage and destruction of the security system of computer network has amounted to be as much as ten billion USD .Confronting with the increasing security threat, One more effective technology is needed to cope with these problems and the intrusion detecting system can provide such assistance for us . As a kind of active security protective technology , Intrusion dectecting system provides the actual protection for the inner and outer attack by intercepting the attack and responding to the intrusion before damaging the network system . with thenetwork technology getting more and more strict and rigourous in its security properties , The intrustion detecting system can provide the comprehensive and complete service from the the stereo and longitudinal and latitudinal and multilayers aspects of the network security , which has become the best choice for the time being . This test began with the introduction of the generalized situation of the intrusion detecting system, including its source, its categories, and its relevant products , and the problem existing for the present has been analyzed and its development trend has been generalized simply . The further study of the detailed inforamtion of Snort has been performed , including its features and construction and detecting procedures and so on , finally, How to install configuration of Snort IDS on the windowns has been introduced correspondily 纯手工翻译,希望满意并采纳,谢谢!