remote access

Definition of remote access in The Network Encyclopedia.

What is Remote Access?

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:

  • File and print services
  • Client/server applications such as database applications
  • Applications for remote network administration

How It Works

  • Remote control:
    Uses a program such as pcAnywhere to take control of the console of a computer remotely. Administrators generally use this method to troubleshoot server problems remotely. However, because the remote connection is often made through a relatively slow analog modem, the bandwidth restriction often makes remote control access slow and jerky. Remote control access provides high security, saves on hardware and licensing costs, and is simple to implement on a network.

     

  • Remote node:
    Uses a remote access device to provide a gateway for users to access file, print, and other services on a company network from remote locations, such as from a laptop while on the road. Remote access gateway devices can be computers running remote access software and connected through multiport serial boards with 4, 8, 12, or more asynchronous communication ports that are connected to analog modem banks or ISDN terminal adapters, or they can be routers with built-in modem or Integrated Services Digital Network (ISDN) functionality. A computer that makes remote access possible is generally called a remote access server, while a router that supports remote access is generally called an access server. Remote node devices can include features such as network address translation (NAT), Dynamic Host Configuration Protocol (DHCP) support, password-based authentication, callback, and basic firewall functionality.

     

Graphic R-4. Remote access.

NOTE

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.

TIP

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:

  • The Windows 2000 Routing and Remote Access console can be used to manage many aspects of Windows NT RRAS routers, but it cannot perform certain tasks such as installing or removing RRAS, configuring RRAS properties, configuring IP–IP tunnels, and so on.
  • The Windows 2000 Routing and Remote Access console cannot be used to manage Windows NT RAS routers. Instead, when you select a Windows NT RAS server using the Windows 2000 RRAS console, the Windows NT administrative tool Remote Access Admin will automatically be opened with the Windows NT RAS server automatically selected.
  • You cannot use the Windows NT RAS administrative tool Remote Access Admin or the Windows NT RRAS administrative tool Routing and RAS Admin to administer Windows 2000 RRAS routers.
  • The netsh command-line utility for administering RRAS on Windows 2000 cannot be used with RAS or RRAS on Windows NT.