Application layer protocols: The rules for implementing the end-user services provided by a network.
Bandwidth: The capacity of a transmission medium.
Bluetooth: A low-power wireless standard used to communicate between devices located quite close to each other, typically no more than 30–50 feet (10–15 meters).
Broadband: Any communication link with a transmission rate exceeding 128,000 bps.
Bulletin board: A shared public file where anyone can post messages and everyone is free to read the postings of others.
Bus topology: A strategy for connecting the nodes of a LAN in which all the nodes are connected to a single shared communication line. If two or more nodes use the link at the same time, the messages collide and are unreadable.
Cable modem: A broadband technology that uses the links that deliver cable TV signals into homes.
Computer network: A set of independent computer systems connected by telecommunication links for the purpose of sharing information and resources.
Dedicated point-to-point lines: Transmission lines that directly connect two machines.
Digital subscriber line (DSL): A broadband technology that uses the same wires that carry regular telephone signals but with a different set of frequencies; DSL transmits digital signals.
Domain Name System (DNS): Application used to convert from a symbolic host name such as macalester.edu to its 32-bit IP address 126.96.36.199.
Electronic commerce (or just e-commerce): General term applied to any use of computers and networking to support the paperless exchange of goods, information, and services in the commercial sector.
End system: An individual computer on a computer network.
Ethernet: A broadband technology that provides dedicated data transmission throughout a building or a campus at rates of either 10 Mbps or 100 Mbps.
Fast Ethernet: A “new and improved” version of Ethernet that transmits at 100 Mbps across coaxial cable, fiber-optic cable, or regular twisted-pair copper wire.
FTP (file transfer protocol): Provides a way to move files around the network quickly and easily.
Framing: Identifying the start and the end of a message.
Gigabit networking: Networks with transmission lines that support speeds in excess of 1 billion bits per second (Gbps).
Host: An individual computer on a computer network.
Hypertext: A collection of documents interconnected by pointers called links.
Internet backbone: An international ISP that provides global coverage.
Internet Service Provider (ISP): A wide-area network whose purpose is to provide access from a private network to the Internet or from an individual’s computer to the Internet.
Internet: A huge interconnected “network of networks” that includes nodes, LANs, WANs, bridges, routers, and multiple levels of ISPs.
IP (Internet Protocol): The network layer in the Internet.
Local area network (LAN): A computer network that connects hardware devices, such as computers, printers, and storage devices, that are all in close proximity.
Logical link control protocols: The rules that ensure that the message traveling across a channel from source to destination arrives correctly.
Medium access control protocols: The rules for determining how to arbitrate ownership of a shared line when multiple nodes want to send at the same time.
Mobile computing: The ability to deliver data to users regardless of where they are located.
Modem: A device that modulates a carrier so that it encodes binary information at one end of the transmission line and then demodulates the carrier at the other end of the transmission line.
Network layer protocols: The rules for delivering a message from the site where it was created to its ultimate destination.
Node: An individual computer on a computer network
Packet: An information block with a fixed maximum size that is transmitted through the network as a single unit.
Physical layer protocols: The rules governing the exchange of binary digits across a physical communication channel, such as a fiber-optic cable, copper wire, or wireless radio channel.
Protocol: A mutually agreed upon set of rules, conventions, and agreements for the efficient and orderly exchange of information.
Repeater: A device that simply amplifies and forwards a signal.
Resource sharing: The ability to share physical resources, such as a printer or storage device, as well as logical resources, such as software and information.
Ring topology: A strategy for connecting the nodes of a LAN, which connects the network nodes in a circular fashion, with messages circulating around the ring in either a clockwise or counter clockwise direction until they reach their destination.
Routing: The process of selecting one specific path for a message.
Shared cable: A form of an Ethernet LAN in which the transmission wire is stretched around and through a building and users tap into the cable at its nearest point using a transceiver.
Social networks: Systems that create communities of users who share common interests and activities and that provide multiple methods of online interaction.
Star topology: A strategy for connecting the nodes of a LAN in which a single central node is connected to all other sites.
Store-and-forward, packet-switched technology: A transmission technology in which a message must “hop” from one node to another to make its way from source to destination.
Switched, dial-up telephone lines: The regular telephone lines used in homes.
Telnet: Software package that allows users to log on remotely to another computer and use it as though it were their own local machine.
TCP (Transport Control Protocol): The primary transport protocol on the Internet.
TCP/IP: The Internet protocol hierarchy.
Transport layer protocols: The rules that create a “program-to-program” delivery service, in which we move messages from a specific program at the source to a specific program at the destination.
URL (Uniform Resource Locator): The worldwide identification of a Web page that is located on a specific host computer on the Internet.
Wide area network (WAN): A computer network that connects devices that are located across town, across the country, or across the ocean.
Wi-Fi (Wireless Fidelity): used to connect a computer to the Internet when it is within range (typically 150–300 feet or 45–90 meters) of a wireless base station.
Wireless data communication: Data communication that uses radio, microwave, and infrared signals to transmit data.
Wireless local access network: A form of wireless data communication in which the user’s computer transmits its message to a local wireless base station that is no more than a few hundred feet from the user’s computer.
Wireless wide-area access network: A form of wireless data communication in which the user’s computer transmits its message to a remote base station provided by a telecommunications company, which may be located many miles away.
World Wide Web: An information system based on the concept of hypertext.