A device that functions as an access control point for users in remote locations connecting to a company's internal network or to an ISP. Also called a "media gateway" or a "remote access server" (RAS), a network access server (NAS) may include its own authentication services or rely on a separate authentication server. A NAS may be a dedicated server or a software service within a regular server. See access control, authentication and remote access concentrator.
NAS Access Control A network access server (NAS) often relies on a separate authentication server such as RADIUS for obtaining authorization to allow or deny access to the network.
Roll Your Own NAS Comtrol developed the first multiport serial card for the PC. Such cards turn a PC into a network access server for modem and ISDN communications or a collector of signals from sensors for data acquisition. The middle card uses RJ-45 jacks to connect to serial lines. The others provide DB-25 ports for modems. (Image courtesy of Comtrol Corporation.)
