Save & ShareNetwork firewall
A network firewall protects a computer network from unauthorized access and is often considered the first line of defense in protecting a computer network against outside threats. On most configurations, data packets entering or leaving a network pass through a firewall, which examines each packet and drops those that do not meet specified criteria. Network firewalls may also be configured to limit how internal users connect externally.
Firewalls, in general, can be implemented as hardware, software, or a combination of both.
