The Cyber Domain

Abstract

Both the Department of Defense (DoD) and the North Atlantic Treaty Organization (NATO) have declared that cyber is a “domain”, co-equal with air, land, and sea. DoD also recognizes space as a domain. Merriam-Webster defines a domain as a sphere of knowledge, influence, or activity. [1] Although DoD does not define “domain”, it does define cyberspace as “A global domain within the information environment consisting of the interdependent network of information technology infrastructures and resident data, including the Internet, telecommunications networks, computer systems, and embedded processors and controllers.” [2] No one has yet proposed what the cyber domain is, where militaries should be operating in cyberspace, and what missions’ militaries should be doing in cyberspace. This article identifies what DoD says their missions are in cyberspace and discusses what areas are appropriate for military operations in cyberspace. Additionally, it argues that militaries must be very careful about what missions they accept in cyberspace, and must circumscribe their forays into cyberspace lest they are overwhelmed by the sheer scope of the domain. CIRCUMSCRIBING THE MILITARY CYBER DOMAIN The military must limit its activities within cyberspace. Just as modern megacities could absorb entire armies, the Internet would swallow the entire cyber capability of not only the DoD but also the capabilities of partners and Allies. It is therefore important to choose how to circumscribe military cyber activities within cyberspace. This is not meant to limit where military cyber units may operate, but rather to limit what functions military cyber resources participate in, thereby preserving cyber capabilities for mission requirements rather than frittering cyber capabilities pursuing wills-o’-the-wisp through cyberspace.