Syntax:       mstsc [/v:computer[:port]]

Explanation:  [/v:computer[:port] specifies the specific remote computer—by name or IP address and port number—to which you want to connect.

Example:      mstsc /v:Cheryl-PC

Notes:        The default port number for Remote Desktop is 3389, but if a different port has been specified, then you can specify a port by using this command.