Validating the Rule set with BDD & Usage with GEM for Improving Efficiency of Firewalls

World is running on internet in real sense since all the important and major tasks of life are carried out through internet. All the major and huge businesses depend on internet but at the same time internet is a big threat for these conglomerates. Because hackers and scams can ruin the online businesses and they could face great deal of data loss. In order to avoid such sort of internet corruption, firewalls are designed as to protect the networks from hackers and scams. Firewall is basically a blockade which restricts the outside forces from accessing your network and attacking your data. By filtering packets the firewalls can improve security and performance. However, as the size of the rule list increases, it becomes difficult to maintain and validate the rules. Ordered binary decision diagrams (BDDs) – a compact method of representing and manipulating Boolean expressions – are a potential method of representing the rules. Geometric Efficient Matching Algorithm (GEM) uses near-linear space, and only needs approximately 13 MB of space for rule-bases of 5,000 rules. Moreover, with use of additional space improving heuristics, the space requirement can be reduced to 2-3 MB for 5,000 rules. This paper presents a new approach not only to analyze and to validate rule sets and also resultant rule sets are passed as an input for Geometric Efficient Matching Algorithm for improving the efficiency of firewalls.