Why use RDP?

• Speed- The RDP Protocol is highly efficient on network bandwidth, meaning that connecting over slower connections like dialup, GSM/GPRS, or 2.5G networks is still a highly usable option, and connecting over high speed connections like Wi-Fi approach the performance of actually sitting at a real desktop.  Unlike other remote access protocols, RDP uses smart and efficient compression and transmission methods allowing a large (1024x768) screen application window to be drawn as fast as a small one, through the use of font caching, bitmap caching, and many different drawing primitives.  To the end user this means a useful experience even on slow wireless connections.
  
• Security- The RDP Protocol connects via SSL, so all the transmission is secure.  No passwords are stored, nor are they transmitted differently than anything else during the transmission, as the receiving end (the Windows computer) takes care of showing the password dialog via the connection.
  
• Screen Size Scalability- As part of the connection, you can choose the desktop size, and the server will scale all windows and controls accordingly to match the desktop size specified.  Mobile TS support several sizes ranging from 320x320 to 1024x768.  This means you can specify to have every window sized to your handheld's smaller screen and not have to continually scroll around to read everything on your desktop, like most other solutions.  Or you have the option to keep your desktop screen larger and scroll around to see the whole area.  The choice is not limited by the technology in this case!

Microsoft Remote Desktop Info