Which of the following is NOT a DoD Cyberspace Domain?

The correct answer is NETSEC because it is not classified as a specific domain within the DoD Cyberspace framework. Instead, NETSEC refers to network security practices and protocols that are utilized to protect information systems and networks across various domains.

On the other hand, SIPR, JWICS, and NIPR are recognized as distinct domains within the DoD cyberspace framework. SIPR (Secret Internet Protocol Router Network) is used for transmitting classified information up to the Secret level, JWICS (Joint Worldwide Intelligence Communications System) is designated for Top Secret intelligence communications, and NIPR (Non-classified Internet Protocol Router Network) supports unclassified communications. Each of these networks serves specific operational and security functions within military and defense communications, reflecting the structured nature of cyberspace in the DoD.