A firewall is a security barrier that is installed between a private network and the public networks (or Internet) at the point of entry to filter all incoming and outgoing packets across it. Firewalls have the responsibility of reviewing any incoming or outgoing packets and reach the decisions about accepting or discarding them. On the basis of contradictory laws, firewalls make decision for each packet in resolving conflicts as the first rule matching the packet. The conventional procedure for constructing firewalls involves a series of rules though inefficient due to the problem of continuity (difficulty in correctly ordering the rules); the completeness problem (difficulty in ensuring thorough scrutiny of all traffic types); and the compactness problem (difficult to keep the number of rules small) because some rules may be redundant and some rules may be combined into one rule. Again, traditional firewalls rely on the concepts of restricted network topology for its operations, and regulation of points of network entry. In particular, firewalls depend on the presumption that node on one side of the entry point of the firewall is to be trusted, and that node on the other side is an enemy. However, this presumption is possible theoretically because of recent advances and access to the Internet. This paper proposes a resolution of packets forwarding problems on computer networks based on distributed firewalls mechanism. The Iptables serve as a policy language, and system management tools. The outcomes showed considerable specification and distribution of resolution policy on Linux operating systems.

Network Firewall Iptables Security Policy RSA CRT