Glossary

LED See light emitting diode.

light emitting diode A small light on a device that is often used to provide status information.

link beat A periodic signal transmitted in Ethernet and IEEE 802.3 Type 10Base-T networks to inform one station of device of the presence of another. It also helps verify the integrity of the network link between them. (Also called “link test pulse”.)

local area network A general- purpose communications network that interconnects a variety of devices within a limited geographical area. A LAN might connect computers on adjacent desks, within a building, or within several buildings of a campus.

M

MAC address See station address.

Mbits/ Megabits per second defined as (1,000,000 bits per second).

medium, media The transmission connection between nodes. Most current LANs use

cables (fiber-optic or copper), although radio and other broadcast media are possible.

N

node A station; a physical device that allows for the transmission of data within a network.

P

packet A bit stream consisting of predefined fields that contain data, addresses, and control information. In the IEEE 802.3 environment this structure is often referred to as the ‘MAC frame”. Packet is the more commonly used term, and originated in the Ethernet environment.

Precision Bus See HP-PB.

protocol The set of rules governing the operation of functional units of a communication system that must be followed if communication is to be achieved.

Glossary

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