Network-based firewalls provide key features used for perimeter security. The primary task of a network firewall is to deny or permit traffic that attempts to enter or leave the network based on explicit preconfigured policies and rules. Firewalls are often deployed in several other parts of the network to provide network segmentation within the corporate infrastructure and also in data centers. The processes used to allow or block traffic may include the following:
Simple packet-filtering techniques
Proxy servers (also known ...