Acceptable Use Policy

This refers to policies that restrict the way in which a network may be used. Usually, a network administrator makes and enforces decisions dealing with acceptable use.

Address Mask

The address mask is used to identify the parts of an IP address that correspond to the different sections (separated by dots). It's also known as the 'subnet mask' since the network portion of an address can be determined by the encoding inherent in an IP address.

Advanced Research Projects Agency Network (ARPANET)

A pioneering long-haul network funded by what's now called DARPA (formerly known as ARPA). It was the foundation on which the Internet was built.

Agent

The part of a system that performs information preparation and exchange on behalf of an application.

Alias

A type of nickname (usually short and easy to remember) that refers to a type of network resource. Aliases are used so you won't have to remember the long and difficult names typical of network resources.

Anonymous FTP

By using the word 'anonymous' as your user ID and your e-mail address as the password when you log in to an FTP site, you can bypass local security checks and gain limited access to public files on the remote computer. This type of access is available on most FTP sites, but not all.

Application

Sometimes known as a client or an 'app' it's a program that performs a specific function. FTP, Mail, Gopher, Mosaic and Telnet clients are the most common examples of Internet applications.

Archie

You'll usually hear this term referred to in the phrase 'archie search'. Archie is a way of automatically gathering, indexing and sometimes even retrieving files on the Internet. Most good archie clients are able to FTP files once you've found the information you're looking for.

Archive

A collection of files stored on a machine. FTP sites are known as archives.

ARPANET

See Advanced Research Projects Agency Network

Asynchronous Transfer Mode (ATM)

A transfer method that dynamically allocates bandwidth using a fixed-sized packet or cell. Also known as fast packet.

ATM

See Asynchronous Transfer Mode

AUP

See Acceptable Use Policy

Authentication

Any process that ensures that users are who they say they are. When you type your name and password, you are authenticated and allowed access.