Any networking technology that gives users access to essential network services from remote locations. Remote access to a company network can be either dial-up access through a modem or dedicated access through a leased line. Remote access typically gives remote users access to the following services on a company network:
Graphic R-4. Remote access.
Microsoft has enabled remote node remote access functionality on both its Windows NT and Windows 2000 operating system platforms to allow remote users to connect to a Windows NT–based or Windows 2000–based network. The Remote Access Service (RAS) of Windows NT provides full-featured remote node services for dial-up networking and virtual private network (VPN) functionality using the RAS and is administered using the administrative tool called Remote Access Admin. The optional Routing and Remote Access Service (RRAS) component for Windows NT 4 adds additional Internet Protocol (IP) routing functionality and is administered using its own tool called Routing and RAS Admin. On the Windows 2000 platform, both dial-up networking and VPN functionality are supported within Routing and Remote Access; they are administered by using either the netsh command-line utility or the Routing and Remote Access console.
A RAS server is often called a RAS router because it has at least one local area network (LAN) and one wide area network (WAN) interface and therefore operates as a router. The same is true of RRAS servers.
In a mixed environment of Windows NT and Windows 2000 RAS and RRAS servers, there are limitations on which tools you can use for administering the various servers: