Dual-homed describes a server or device that is simultaneously connected to two separate networks — typically the internal network and a DMZ or the internet.
Dual-homed hosts can function as simple firewalls or gateways but present an elevated security risk: if the device is compromised, the attacker potentially gains access to both networks. Stricter hardening requirements therefore apply to dual-homed systems. Modern architectures prefer dedicated firewalls and network segmentation. Where dual-homing is unavoidable (e.g., certain print servers or backup gateways), the configuration must be audited regularly.