Improving Performance of CrossDomain Firewalls in MultiFirewall System

Abstract

Abstract-Firewall is used to protect local network from outside untrusted public network or Internet. Every packet coming to and going out from network is inspected at Firewall. Local network policies are converted into rules and stored in firewall. It is used to restrict access of the external network into local network and vice versa. Packets are checked against the rules serially. Therefore increase in the number of rules decreases the firewall performance. The key thing in performance improvement is to reduce number of firewall rules. Optimization helps to reduce number of rules by removing anomalies and redundancies in the rule list. It is observed that only reducing number of rules is not sufficient as the major time is consumed in rule verification. Therefore to reduce time of rule checking fast verification method is used. Prior work focuses on either Intrafirewall optimization or Interfirewall optimization within single administrative domain. In cross-domain firewall optimization key thing is to keep rules secure from others as they contain confidential information which can be exploited by attackers. The proposed system implements cross-domain firewall rule optimization. For optimization multi-firewall environment is considered. Then optimized rule set is converted to Binary Tree Firewall (BTF) so as to reduce packet checking time and improve firewall performance further.