29-08-2017, 02:21 PM
In computing, a firewall is a network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules. A firewall typically establishes a barrier between a trusted and secure internal network and another external network, such as the Internet, which is not supposed to be secure or trusted.
Firewalls are often categorized as network firewalls or host-based firewalls. Network firewalls filter traffic between two or more networks; are software devices that run on general-purpose hardware or hardware-based firewall computer devices. Host-based firewalls provide a layer of software on a host that controls network traffic on and off that single machine.
Firewall devices can also provide other functionality to the internal network they protect, such as acting as a DHCP or VPN server for that network.
Firewalls are often categorized as network firewalls or host-based firewalls. Network firewalls filter traffic between two or more networks; are software devices that run on general-purpose hardware or hardware-based firewall computer devices. Host-based firewalls provide a layer of software on a host that controls network traffic on and off that single machine.
Firewall devices can also provide other functionality to the internal network they protect, such as acting as a DHCP or VPN server for that network.