Any entity on a network that can be managed, such as a system, repeater, router, gateway, switch or firewall. A computer or other addressable device attached to a network; a host.

An individual computer connected to a network. Also, a system or application (such as a Web browser or user agent) that requests a service from another computer (the server) and is used to access files o

A computer in a network that manages the network resources and provides, or serves, information to clients.

A group of computers connected within a confined geographic area.

A group of computers connected over an expansive geographic area so their users can share files and services.

A worldwide network of interconnected networks.

A U.S. Department of Defense agency that created the first global computer network.

A computer network, funded by ARPA, that served as the basis for early networking research and was the backbone during the development of the Internet.

An independent agency of the U.S. government that promotes the advancement of science and engineering.

The highest level in the computer network hierarchy, to which smaller networks typically connect.

A node on a network that serves as a portal to other networks.

A set of software programs that enables users to access resources on the Internet via hypertext documents.

Highlighted or underlined text in a Web page that, when clicked, links the user to another location or Web page.

Highlighted or underlined text in a Web page that, when clicked, links the user to another location or Web page.

A World Wide Web server and its content; includes multiple Web pages.

A software application that enables users to access and view Web pages on the Internet.

A suite of protocols that turns data into blocks of information called packets, which are then sent across the Internet. The standard protocol used by the Internet.

Data processed by protocols so it can be sent across a network.

A device that routes packets between networks based on network-layer addresses; determines the best path across a network. Also used to connect separate LANs to form a WAN.

An organization that maintains a gateway to the Internet and rents access to customers on a per-use or subscription basis.

An analog device that enables computers to communicate over telephone lines by translating digital data into audio/ analog signals (on the sending computer) and then back into digital form (on the receiving computer).

A communication standard for sending voice, video or data over digital telephone lines.

The amount of information, sometimes called traffic, that can be carried on a network at one time. The total capacity of a line. Also, the rate of data transfer over a network connection; measured in bits per second.

A circuit board within a computer's central processing unit that serves as the interface enabling the computer to connect to a network.

A device that enables wireless systems to communicate with each other, provided that they are on the same network.

A definition or format that has been approved by a recognized standards organization.

A high-speed direct Internet connection that uses all-digital networks.

Collectively, the variations of Digital Subscriber Line (DSL), which include ADSL, RADSL and HDSL.

Wireless phone network capable of delivering highspeed broadband Internet access to mobile devices.

A device that connects a wireless local area network to a wireless phone network at broadband speeds.

The data transmission standard for the Internet. Every computer connected to the Internet has its own IP address, which enables a packet of data to be delivered to a specific computer.

The international organization responsible for allocation of IP addresses. Part of the Internet Corporation for Assigned Names and Numbers (ICANN).

A base-16 number system that allows large numbers to be displayed by fewer characters than if the number were displayed in the regular base-10 system. In hexadecimal, the number 10 is represented as the letter A, 15 is represented as F, and 16 is represented as 10.

A protocol that allows a computer to connect to the Internet over a phone line.

A protocol that implements PPP on top of the Ethernet architecture to connect an entire network to the Internet.

The protocol for transporting HTML documents across the Internet.

An Internet protocol used to transfer files between computers; allows file transfer without corruption or alteration.

The Internet standard protocol for transferring e-mail messages from one computer to another.

A protocol that resides on an incoming mail server. The current version is POP3.

A protocol that resides on an incoming mail server. Similar to POP, but is more powerful. Allows sharing of mailboxes and multiple mail server access. The current version is IMAP4.

A collection of thousands of Internet computers, newsgroups and newsgroup members using Network News Transfer Protocol (NNTP) to exchange information.

On Usenet, a subject or other topical interest group whose members exchange ideas and opinions. Participants post and receive messages via a news server.

The Internet protocol used by news servers that enables the exchange of newsgroup (Usenet) articles.

A system that maps uniquely hierarchical names to specific Internet addresses.

An IP address represented in words.

A computer that other computers can use to gain information. In network architecture, a host is a client or workstation.

The complete domain name of an Internet computer, such as www.CIWcertified. com.

The group into which a domain is categorized, by common topic (company, educational institution) and/or geography (country, state).

A server at the highest level of the Domain Name System.

A server that resolves domain names into IP addresses.

A hosting service that allows a company to host its domain name on a third-party ISP server.

A hosting service that allows multiple entities to share portions of the same domain name.