Concepts / Firewalls

Firewalls

DMZ

Also called demilitarized zone, perimeter network, screened subnet

A network apart for the servers the internet may reach, so breaking into one opens nothing behind it.

Public servers sit on their own network, and the firewall allows the internet in to them only for what they serve, and them out only to what they need (a database, say). Whoever takes over a DMZ server finds the office and the rest closed: the damage stays in the zone.

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