Firewall is a Proxy or Gateway Network device used for security that is an Observer and can perform Monitoring and may be able to controls incoming and outgoing network traffic based on predetermined Access Control Policy

Firewall typically establishes a barrier between a trusted internal network and untrusted external network such as the Internet.

Firewall are often categorized as either Network firewalls or Host-based Firewall. Network Firewall filter network traffic between two or more networks and run on Network devices. Host-based Firewall run on host computers and control network traffic in and out of those machines.

Many Types#

There are many types variances within Firewall. Consult the references or "Google" to find more.

More Information#

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