standard RDP port is 3389 (Remote Desktop Protocol)
Port 3389 is the only port you need to open. Windows will attempt to stream sound through User Datagram Protocol (UDP) first. If no port is available for UDP, sound will stream through a virtual channel in Remote Desktop Protocol, which uses port 3389. http://www.microsoft.com/windowsxp/using/mobility/rdfaq.mspx
The standard port that Remote Desktop Protocol (RDP) uses is port 3389. An example of an application that uses this port is TeamViewer. Applications such as Teamviewer allow a person to look on his own computer from, for example, his/her mobile phone or tablet.
Microsoft Remote Desktop
it's 3389
By default the server listens on TCP port 3389 http://en.wikipedia.org/wiki/Remote_Desktop_Protocol . It can be configured to use different ports. If you are having problems connecting to some host, it might be possible that the host is behind a router and those ports are blocked. you can use : http://portforward.com/help/portcheck.htm to see if the port is open
Windows XP uses port 3389 as default for Remote Desktop connections
3389 is the remote desktop protocol port.
The default listening ports for Windows XP Remote Desktop are TCP port 3389 and UDP port 3389. Remote Desktop Protocol is available for several versions of Microsoft Windows as well as some alternate OS offerings.
Remote assistance port 3389 should be opened.
RDP. Remote Desktop Protocol (RDP) is used by the Windows Remote Desktop and Remote Assistance utilities to connect to and control a remote computer. Remote Desktop and Remote Assistance listen at port 3389.
RDP. Remote desktop protocol in Microsoft systems. Also known as terminal services on port 3389.