Abstract: As the use of web side information for critical services has increased, the sophistication of attacks against these applications has grown as well. To protect web applications several intrusion detection systems have been proposed. In this paper, several techniques which are meant for detect ion of web application related attacks. The Intrusion detection system provides the following: .Monitoring and analyzing of user and system activity. Auditing of system configurations and vulnerabilities. Assessing the integrity of the files and critical system. Statistical analysis of activity patterns. Abnormal activity analysis. Operating system audit.
Keywords: Side information Intrusion detection operating system audit.