Windows Server 2019 Remote Desktop Services CAL 2019 Single User. Remote Desktop Services (formerly known as Terminal Services) provides functionality similar to a terminal-based, centralized host, or mainframe, environment in which multiple terminals connect to a host computer. Each terminal provides a conduit for input and output between a user and the host computer. A user can log on at a terminal, and then run applications on the host computer, accessing files, databases, network resources, and so on. Each terminal session is independent, with the host operating system managing conflicts between multiple users contending for shared resources. The primary difference between Remote Desktop Services and the traditional mainframe environment is that the dumb terminals in a mainframe environment only provide character-based input and output. A Remote Desktop Connection (RDC) client or emulator provides a complete graphical user interface including a Windows operating system desktop and support for a variety of input devices, such as a keyboard and mouse. 2019 Remote Desktop Services Cals are backwards compatible with Server 2016. Remote Services lets you deliver Windows-based applications, or the Windows desktop itself, to virtually any computing device - including those that cannot run Windows. Minimum to start an Agreement with Microsoft is 5 pieces. Sent via Email only! CALL YOUR SALES REP TO PURCHASE MUST PROVIDE END USER INFORMATION.