500-3
AR25-2 is Information Assurance. (See the related link below)"This regulation establishes information assurance (IA) policy, roles, and responsibilities. It assigns responsibilities forall Headquarters, Department of the Army (HQDA) staff, commanders, directors, IA personnel, users, and developersfor achieving acceptable levels of IA in the engineering, implementation, operation, and maintenance (EIO&M) for allinformation systems (ISs) across the U.S. Army Enterprise Infostructure (AEI)."
AR 500-3