An intrusive way to detect coordinated attacks using CIDS

Coordinated Attacks are large scale attacks that have been intruding various networks and harming several hosts at the same time. These attacks are posing malicious activities being performed at the host site and result in compromising several hosts. In order to capture the evidence of such type of attacks, a cooperative approach i.e. Collaborative Intrusion Detection System is been considered. The attacks been performed at various sites is been captured through alert correlation system of a CIDS. This paper is a study of how alerts are been normalized, filtered and reduced using an Alert Correlation System in a Collaborative Intrusion Detection System (CIDS).