Widening distribution Conventional firewalls rely on topology to work. They restrict traffic at a specific point in order to control and examine everything coming in and going out. In an active e-business environment, this can result in a bottleneck. Server-resident firewalls, on the other hand, distribute firewall security across multiple processors, providing virtually unlimited scalability. At the same time, they eliminate the single point of failure presented by the conventional perimeter firewall.
Distributed firewalls provide central policy definition and security monitoring.
Policy definition should typically include the ability to push policy to hundreds or thousands of end users' hosts or application servers and to have the firewall agent work as a background service. Security monitoring typically includes log aggregation and analysis, firewall statistics and fine-grained remote monitoring of individual hosts, if needed. Server-resident firewalls are a subset of centrally managed, distributed firewalls. Host-resident firewalls harden infrastructure servers against attacks, compensating for the inherent security weaknesses of all network operating systems. Information and application servers can be hidden from unwanted user access by silently dropping incoming connection attempts.