WINDOWS SERVER 2012 STANDARD EDITION
The Windows Server 2012 R2 Standard edition of windows server is used for medium to large businesses that require additional features not present in the Foundation & Essential edition. The Standard edition is able to support an unlimited amount of users, as long as the required user licenses have been purchased.
Advanced features such as certificate services role, Hyper V, RODC (Read Only Domain Controller), IPAM (IP Address Management), Data deduplication, server core, failover clustering and more, are available to Windows Server 2012 Standard edition. We should note that the Standard edition supports up to 2 Virtual Machines.