In networking terminology, the DMZ network is defined as a network which is less restricted as opposed to corporate network (LAN) which can never be accessible to outside world directly. It is always recommended that all public servers like web server, ftp server etc be places in a physically separate network from corporate network. This is to eliminate possibility of compromising a corporate system if any of the public servers is compromised.

The Network Firewall plays a key role in controlling the in-bound connections. In this case, any connection coming from Internet is denied if it attempt to reach LAN/corporate network. but for DMZ network, specific Firewall policies are set up to allow specific connections like web (HTTP), FTP to reach DMZ network where public servers are placed.

Modern day routers come with three ethernet ports: CORP, DMZ and Internet. However Home routers may not have DMZ port.