The Microsoft Remote Desktop Protocol (RDP) provides remote display and input capabilities over network connections for Windows-based applications running on a server. RDP is designed to support different types of network topologies and multiple LAN protocols.
RDP is based on, and is an extension of, the existing ITU T.120 family of protocols. RDP is a multiple-channel capable protocol that allows for separate virtual channels for carrying encrypted device communication and presentation data from the server, as well as encrypted client mouse and keyboard data. RDP provides an extensible base and supports up to 64,000 separate channels for data transmission and provisions for multipoint transmission.
On the server, RDP uses its own video driver to render display output by constructing the rendering information into network packets. RDP then sends the packets over the network to the client. On the client, RDP receives rendering data and interprets the packets into corresponding Graphics Device Interface (GDI) API calls. For the input path, client mouse and keyboard events are redirected from the client to the server. On the server, RDP uses its own virtual keyboard and mouse driver to receive these keyboard and mouse events.
The RDP 4.0 protocol was introduced with Windows NT Server 4.0, Terminal Server Edition. Windows 2000 Terminal Services introduced RDP 5.0, which provides enhanced performance over low-speed connections. Windows XP uses RDP 5.1 for Remote Desktop Connection and for Remote Assistance, which added support for displays using millions of colors, reduced bandwidth requirements, and redirection of sound, drives, ports, and network printers. These enhancements allow sounds that occur on the remote computer to be heard on the local computer, and they make the disk drives on the local computer available to the remote computer for easy file transfer.
Remote Desktop Connection Client for Mac can establish connections to servers running RDP 5.1 and earlier.
Related topics
Improve the performance of connections
Connect to a specific network port
Connect to a Windows console session
Differences between the Windows and Macintosh versions