Abbreviated as NAS, a
network access server is an
access
gateway between an external
communications network
and an internal network. A common use of NAS is by Internet service providers
(
ISP) where the user dials into the ISP and is given
access to the
Internet after being authorized by the
access server. Network access server (NAS) is also referred to as a
remote access server (RAS) or as a media
gateway. The
IETF Network Access Server Requirements
Working Group is responsible for defining the requirements for modern network
access servers.