Firewalls | Deploy and Manage

Deploy
Once testing is complete and all issues have been resolved, the next phase of the firewall planning and implementation model is deployment, which should be done in accordance with organization policies.

Before deploying the firewall, administrators should notify users or owners of potentially affected systems of the planned deployment, and instruct them who to notify if they encounter any problems.Any changes required to other equipment, such as changing default routes, should [..]

Firewalls – Dedicated Proxy Servers

Dedicated proxy servers differ from application-proxy and circuit-level gateways in that while they retain proxy control of traffic, they do not have firewalling capabilities.

Although dedicated proxy servers are not firewalls, they are described in this section because of their close relationship to application-proxy gateway firewalls and circuit-level gateway firewalls. Many proxies are application-specific, and some actually perform analysis and [..]

Firewalls | Packet Filtering

The most basic feature of a firewall is the packet filter. Firewalls that are only packet filters—also known as stateless inspection firewalls—are essentially routing devices that provide access control functionality for host addresses and communication sessions. Unlike more advanced filters, packet filters are not concerned about the content of packets.

Their access control functionality is governed by a set of directives referred to as a ruleset. Packet filtering capabilities are built [..]