The US Department of Defense announced today that it is to standardize on Windows 10. Over the course of the next year, some 4 million systems will be upgraded to Microsoft's latest operating system in what must be the largest enterprise deployment of the operating system worldwide.

This is a followup to a November order to upgrade systems in Combatant Commands, Service Agencies, and Field Activities to the operating system. The rationale is the government's desire to protect better against security breaches and reduce IT costs by streamlining on a single platform. Windows 10 is better protected against security flaws than its predecessors, making it a tougher target for attackers.

In tandem with this, the government has given the Surface 3, Surface Pro 3, Surface Pro 4, and Surface Book all the relevant certifications to allow those systems to be included on the Defense Information Systems Agency (DISA) Unified Capabilities (UC) Approved Products List (APL). This means that DoD agencies can now buy and use Surface family hardware in its deployments.

While concerns over Windows 10's privacy policy and network connectivity have been a lingering feature of the operating system's release, this announcement suggests that at least one large, security-sensitive enterprise operator is satisfied with the controls that Microsoft provides.