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Bit rate

The amount of bits that pass in given amount of time

Bit/sec

Bits per second

BOOTP

Bootstrap Protocol. Allows for computers to be booted up and given an IP address with

no user intervention

Bottleneck

A time during processes when something causes the process to slowdown or stop all

together

Broadband

A wide band of frequencies available for transmitting data

Broadcast

Transmitting data in all directions at once

Browser

A program that allows you to access resources on the web and provides them to you

graphically

C

Cable modem

A device that allows you to connect a computer up to a coaxial cable and receive Internet

access from your Cable provider

CardBus

A newer version of the PC Card or PCMCIA interface. It supports a 32-bit data path,

DMA, and consumes less voltage

CAT 5

Category 5. Used for 10/100 Mbps or 1Gbps Ethernet connections

Client

A program or user that requests data from a server

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Collision

When do two devices on the same Ethernet network try and transmit data at the exact

same time.

Cookie

Information that is stored on the hard drive of your computer that holds your preferences

to the site that gave your computer the cookie

D

Data

Information that has been translated into binary so that it can be processed or moved to

another device

Data Encryption Standard

Uses a randomly selected 56-bit key that must be known by both the sender and the

receiver when information is exchanged

Database

Organizes information so that it can be managed updated, as well as easily accessed by

users or applications.

Data-Link layer

The second layer of the OSI model. Controls the movement of data on the physical link of

a network

DB-25

A 25 pin male connector for attaching External modems or RS-232 serial devices

DB-9

A 9 pin connector for RS-232 connections

dBd

Decibels related to dipole antenna

dBi

Decibels relative to isotropic radiator

dBm

Decibels relative to one milliwatt

Decrypt

To unscramble an encrypted message back into plain text

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Default

A predetermined value or setting that is used by a program when no user input has been

entered for this value or setting

Demilitarized zone

DMZ: A single computer or group of computers that can be accessed by both users on

the Internet as well as users on the Local Network, but that is not protected by the same

security as the Local Network.

DHCP

Dynamic Host Configuration Protocol: Used to automatically assign IP addresses from a

predefined pool of addresses to computers or devices that request them

Digital certificate:

An electronic method of providing credentials to a server in order to have access to it or a

network

Direct Sequence Spread Spectrum

DSSS: Modulation technique used by 802.11b wireless devices

DMZ

"Demilitarized Zone". A computer that logically sits in a "no-mans land" between the LAN

and the WAN. The DMZ computer trades some of the protection of the router's security

mechanisms for the convenience of being directly addressable from the Internet.

DNS

Domain Name System: Translates Domain Names to IP addresses

Domain name

A name that is associated with an IP address

Download

To send a request from one computer to another and have the file transmitted back to the

requesting computer

DSL

Digital Subscriber Line. High bandwidth Internet connection over telephone lines

Duplex

Sending and Receiving data transmissions at the sane time

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Dynamic DNS service

Dynamic DNS is provided by companies to allow users with Dynamic IP addresses to

obtain a Domain Name that will always by linked to their changing IP address. The IP

address is updated by either client software running on a computer or by a router that

supports Dynamic DNS, whenever the IP address changes

Dynamic IP address

IP address that is assigned by a DHCP server and that may change. Cable Internet

providers usually use this method to assign IP addresses to their customers.

E

EAP

Extensible Authentication Protocol

Email

Electronic Mail is a computer-stored message that is transmitted over the Internet

Encryption

Converting data into cyphertext so that it cannot be easily read

Ethernet

The most widely used technology for Local Area Networks.

F

Fiber optic

A way of sending data through light impulses over glass or plastic wire or fiber

File server

A computer on a network that stores data so that the other computers on the network can

all access it

File sharing

Allowing data from computers on a network to be accessed by other computers on the

network with different levels of access rights

Firewall

A device that protects resources of the Local Area Network from unauthorized users

outside of the local network

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Firmware

Programming that is inserted into a hardware device that tells it how to function

Fragmentation

Breaking up data into smaller pieces to make it easier to store

FTP

File Transfer Protocol. Easiest way to transfer files between computers on the Internet

Full-duplex

Sending and Receiving data at the same time

G

Gain

The amount an amplifier boosts the wireless signal

Gateway

A device that connects your network to another, like the internet

Gbps

Gigabits per second

Gigabit Ethernet

Transmission technology that provides a data rate of 1 billion bits per second

GUI

Graphical user interface

H

H.323

A standard that provides consistency of voice and video transmissions and compatibility

for videoconferencing devices

Half-duplex

Data cannot be transmitted and received at the same time

Hashing

Transforming a string of characters into a shorter string with a predefined length