Firewall rules analysis

Abstract

In this paper, we propose a method to analyze the firewall policy or rule-set using Relational Algebra and Raining 2D-Box Model. It can discover all the anomalies in the firewall rule-set in the format that is usually used by many firewall products such as Cisco Access Control List, IPTABLES, IPCHAINS and Check Point Firewall-1. While the existing analyzing methods consider the anomalies between any two rules in the firewall rule-set, we consider more than two rules together at the same time to discover the anomaly. Therefore we can find all the hidden anomalies in the firewall rule-set. Results from analyzing can be used with the proposed rules-combination method presented in this paper, to minimize the firewall rule without changing the policy. Finally, we have developed an application based on the proposed analyzing method. This application could help administrator to analyze and modify a complex firewall policy with less error.