D
Data
Information that has been translated into binary so that it can be processed or moved to another device
Data-Link layer
The second layer of the OSI model. Controls the movement of data on the physical link of a network 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
Default
A predetermined value or setting that is used by a program when no user input has been entered for this value or setting
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
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
Duplex
Sending and Receiving data transmissions at the sane time
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
Encryption
Converting data into cyphertext so that it cannot be easily read
Ethernet
The most widely used technology for Local Area Networks.
F
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
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
Sending and Receiving data at the same time
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