Documentation > Vocabulary
Below is a list of words (or acronyms) and their meanings which are used throughout this site.
Radius - Refers to a common protocol used by many network appliances (such as terminal servers) to send authentication requests and/or accounting details. A Radius client can be a program running on a PC, or a piece of hardware such as a Dialup Server/NAS (more common).
When a user attempts to login to a Dialup Server which supports radius, the dialup server sends a request, using the radius protocol, to the Radius server (an application running on a computer). The server then checks if the authentication details given are valid, and if so sends a reply to the dialup server (client), which indicates the user is valid. The server also takes this opportunity to send along any attributes such as session timeouts, and ip addresses which should be assigned to the user.
The dialup server would permit the login as well as enforce the appropriate attributes. Once the user disconnects, the dialup server would send an accounting packet to the server, which the server might store in a log file or database.
Accounting - This refers to the accounting information sent back from the NAS, containing information about the session such as user details, session time, and bytes transferred.
NAS - Network Access Server, a system that provides access to a network. In some cases also know as a RAS, Remote Access Server. Commonly refers to a terminal server which sends authentication and/or accounting information to a Radius server.
RAS - Remote Access Server.
In most cases, exactly the same as a NAS.
PAP - Peer Authentication Protocol - passwords are transmitted in cleartext
CHAP - Challenge Authentication Protocol - passwords are transmitted encrypted, along with a challenge which is used (alongside a locally stored plaintext password), to decrypt the supplied password.
MySQL - A popular SQL database program which can be found here. It is a common source for retrieving and storing records.
Perl - A interpereted language. Popular for writing text and web based applications, but certainly not limited to those tasks.
SQL - Structured Query Language, a commonly used language by many databases such as Oracle, MySQL and PostgreSQL as a way for accessing and storing data in a database. This uniformity often means that applications which talk to a database via SQL can be converted to a database with little or no modification.
Attributes - In the world of Radius attributes refer to settings both defined in the config files and, those passed between the radius client and server (such as the 'User-Name' attribute, or 'Framed-IP-Address' attribute).
Terminal Server - A server which handles logins of some kind, including but not limited to a dialup server for handling users connecting via modem.