All the major operating systems include built-in support for remote access. They provide both the access methods and security protocols necessary to secure the connection and data transfers.
Remote Access Service (RAS)
RAS is a remote access solution included with Windows Server products. RAS is a feature-rich, easy-to-configure, and easy-to-use method of configuring remote access.
Any system that supports the appropriate dial-in protocols, such as PPP, can connect to a RAS server. Most commonly, the clients are Windows systems that use the dial-up networking feature; but any operating system that supports dial-up client software will work. Connection to a RAS server can be made over a standard phone line, using a modem, over a network, or via an ISDN connection.
RAS supports remote connectivity from all the major client operating systems available today, including all newer Windows OSs:
Windows 2000 Professionalbased clients
Windows XP Homebased clients
Windows XP Professionalbased clients
Although the system is called RAS, the underlying technologies that enable the RAS process are dial-up protocols such as Serial Line Internet Protocol (SLIP) and Point-to-Point Protocol (PPP).