Which architecture uses more than two interfaces to connect networks with multiple boundaries?

• A. DMZ
• B. Extranet
• C. Multi-Homed Firewall
• D. Dual-Home Firewall

Answer: (C)

Connecting multiple networks with more than two boundaries requires a firewall setup that has more than two network interfaces. This is what a multi-homed firewall provides: it attaches to three or more networks, giving distinct paths between internal networks, the Internet, and any additional zones such as a DMZ or partner networks. With separate interfaces, you can enforce different security policies for traffic moving between each network pair, which enhances segmentation and defense in depth. A DMZ is a security zone for publicly accessible services and can be implemented with such a firewall, but the term DMZ itself doesn’t specify the number of interfaces. An extranet concerns external partners’ access, not how many interfaces the firewall uses. A dual-homed firewall usually has two interfaces, which does not meet the requirement of more than two.