In today’s world of increasing cyber-attacks, we cannot live without firewalls. A firewall is a hardware or software network security system designed to restrict unauthorized traffic to the restricted segment of a network. In a typical scenario, services that are not supposed to be reachable outside a subnet are restricted in a firewall. There are

SNORT, is a free and open source Intrusion Detection and Prevention System developed by Sourcefire. Snort utilizes the combination of signatures, protocol and anomaly based inspection to detect malicious traffic passing through. Snort performs packet logging, log analysis, content searching and matching on real time basis to be able to detect attacks such as buffer