Remote Access Service - AbsoluteAstronomy.com

Remote Access Services refers to any combination of hardware and software to enable the remote access tools or information that typically reside on a network of IT devices. A RAS server is a specialized computer which aggregates multiple communication channels together. Because these channels are bidirectional, two models emerge: Multiple entities connecting to a single resource, and a single entity connecting to multiple resources. Both of these models are widely used. Both physical and virtual resources can be provided through a RAS server: centralized computing can provide multiple users access to a remote virtual operating system. Access Providers often use RAS servers to terminate physical connections to their customers, for example customers who get Internet through some form of modem.

Originally coined by Microsoft when referring to their built-in NT remote access tools, RAS was a service provided by Windows NT

Windows NT

Windows NT is a family of operating systems produced by Microsoft, the first version of which was released in July 1993. It was a powerful high-level-language-based, processor-independent, multiprocessing, multiuser operating system with features comparable to Unix. It was intended to complement...

which allows most of the services which would be available on a network

Computer network

A computer network, often simply referred to as a network, is a collection of hardware components and computers interconnected by communication channels that allow sharing of resources and information....

to be accessed over a modem

Modem

A modem is a device that modulates an analog carrier signal to encode digital information, and also demodulates such a carrier signal to decode the transmitted information. The goal is to produce a signal that can be transmitted easily and decoded to reproduce the original digital data...

link. The service includes support for dialup and logon

Logon

Logon may refer to:*The Logone River in Chad, Africa*in computing, the process of login...

, presents the same network interface as the normal network drivers (albeit slightly slower). It is not necessary to run Windows NT on the client

Client (computing)

A client is an application or system that accesses a service made available by a server. The server is often on another computer system, in which case the client accesses the service by way of a network....

- there are client versions for other Windows

Microsoft Windows

Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...

operating systems.

A feature built into Windows NT

Windows NT

enables users to log into an NT-based LAN

Län

Län and lääni refer to the administrative divisions used in Sweden and previously in Finland. The provinces of Finland were abolished on January 1, 2010....

using a modem, X.25

X.25

X.25 is an ITU-T standard protocol suite for packet switched wide area network communication. An X.25 WAN consists of packet-switching exchange nodes as the networking hardware, and leased lines, Plain old telephone service connections or ISDN connections as physical links...

connection or WAN

Wide area network

A wide area network is a telecommunication network that covers a broad area . Business and government entities utilize WANs to relay data among employees, clients, buyers, and suppliers from various geographical locations...

link. RAS works with several major network protocols, including TCP/IP, IPX

IPX

Internetwork Packet Exchange is the OSI-model Network layer protocol in the IPX/SPX protocol stack.The IPX/SPXM protocol stack is supported by Novell's NetWare network operating system. Because of Netware's popularity through the late 1980s into the mid 1990s, IPX became a popular internetworking...

, and NBF.

To use RAS from a remote node, you need a RAS client program, which is built into most versions of Windows, or any PPP

Point-to-Point Protocol

In networking, the Point-to-Point Protocol is a data link protocol commonly used in establishing a direct connection between two networking nodes...

client software. For example, most remote control programs work with RAS.

Starting in the mid-1990s, several manufacturers such as U.S. Robotics

U.S. Robotics

USRobotics Corporation is a company that makes computer modems and related products. It sold high-speed modems in the 1980s, and had a reputation for high quality and compatibility. With the reduced usage of voiceband modems in North America in the early 21st century, USR is now one of the few...

produced "modem terminal servers". Instead of having RS-232

RS-232

In telecommunications, RS-232 is the traditional name for a series of standards for serial binary single-ended data and control signals connecting between a DTE and a DCE . It is commonly used in computer serial ports...

ports, these would directly incorporate an analog modem

Modem

. These devices were commonly used by Internet service providers to allow consumer dial-up. Modern versions interface to an ISDN PRI

PRI

PRI may refer to:* Pacific Research Institute, a California-based free market think tank* Paleontological Research Institution, Ithaca, New York* Panchayati Raj Institutions* Penal Reform International, a non-governmental organization...

instead of having analog modem ports.

See also