Which term is considered the front line defense between DoD and the Internet, safeguarding against cyber threats and unauthorized access?

Which term is considered the front line defense between DoD and the Internet, safeguarding against cyber threats and unauthorized access?

• A. USAF Gateway Router - IP/MPLS
• B. SIPRNet Gateways
• C. Proxy
• D. IMS

Answer: (A)

The boundary device that sits at the edge where the DoD network meets the Internet serves as the first line of defense, screening and controlling traffic before it enters the internal network. A gateway router performs this border role by directing legitimate traffic, applying security policies like access control lists, NAT, and route filtering, and ensuring only authorized paths cross into the DoD network. It’s mounted at the point where external networks and DoD networks interconnect, making it the natural front door for inbound and outbound traffic. The other options fit specific functions that aren’t primarily about that edge defense. A proxy handles application-level filtering and caching, which is important but serves a different role from the router that enforces the initial boundary policy. SIPRNet gateways connect DoD networks to the SIPRNet (a separate, highly classified network) rather than to the general Internet boundary. IMS is a telecom framework and not a security boundary device.

The boundary device that sits at the edge where the DoD network meets the Internet serves as the first line of defense, screening and controlling traffic before it enters the internal network. A gateway router performs this border role by directing legitimate traffic, applying security policies like access control lists, NAT, and route filtering, and ensuring only authorized paths cross into the DoD network. It’s mounted at the point where external networks and DoD networks interconnect, making it the natural front door for inbound and outbound traffic.

The other options fit specific functions that aren’t primarily about that edge defense. A proxy handles application-level filtering and caching, which is important but serves a different role from the router that enforces the initial boundary policy. SIPRNet gateways connect DoD networks to the SIPRNet (a separate, highly classified network) rather than to the general Internet boundary. IMS is a telecom framework and not a security boundary device.