Remote Access Servers are outside a Local Area Network (LAN) but require access from outside to within the LAN.
In doing this, it allows users to access files & print services on the Local Area Network from the outside.
A good example of this is a employee of a company who is working away from home, but requires access to his employers internal computer network. He would gain access via the means of a internet connection, sending a request the Remote Access Server to connect up.
The RAS would then authenticate the user via means of a password query. Once authenticated the employee would be able to access shared drives and printers as if we were actually working on a computer in the office.
Some companies use a Remote Access Server to connect up different branches, often employing a dedicated Integrated Services Digital Network (ISDN) line.
Sometimes called a communication server, a Remote Access Server usually includes or is connected via a firewall server to maintain security and a router to connect the RAS to the internet network.
A remote access server may also be arranged as a part of a Virtual Private Network (VPN)
