Stateful Multilayer Inspection Firewall

Abstract

access control based on sender or receiver address • access control based on services requested • hiding the internal network, e.g. topology, addresses, etc. • virus checking on incoming files • authentication based on the source of traffic • logging of Internet activities Placement of firewall components: (1) packet filter (2) circuit-level proxy (3) application-level proxy Packet Filtering: Packet filtering is a network security mechanism that works by controlling what data can flow to and from a network. The data that flows is in the form of packets. Packet filtering firewall allows only those packets to pass, which are allowed as per your firewall policy. Each packet passing through is inspected and then the firewall decides to pass it or not. The packet filtering can be divided into two parts: I. Stateless packet filtering. II. Statefull packet filtering.