Network Topology

The public Internet is considered insecure. The firewall defines a "demilitarized zone" which is isolated from both the public Internet and the internal network, and is considered to be somewhat secure though not completely trusted. If compromised, only services on its small network will be affected. The internal network is usually considered trusted and may have additional services (e.g., a data warehouse). But beware: some internal networks are not to be trusted any more than the public Internet!