Security Appliances & Firewalls
A firewall is a network security device that monitors incoming and outgoing network traffic and decides whetherto allow or block specific traffic based on a defined set of security rules.
Proxy firewall
Proxy servers can provide additional functionality such as content caching and security by preventing direct connections from outside the network.
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Unified threat management (UTM) firewall
A UTM device typically combines, in a loosely coupled way, the functions of a stateful inspection firewall with intrusion prevention and antivirus.
Stateful inspection firewall
A stateful inspection firewall allows or blocks traffic based on state, port, and protocol. It monitors all activity from the opening of a connection until it is closed.
