Capitulo 7

GLOSSARY

RF:
radio frequency. electromagnetic waves generated by AC and sent to an antenna within the electromagnetic spectrum.

IrDA:
infrared data association. defines protocol standards for the short range exchange of data over infrared light for uses such as PANs.

ISM:
industrial, scientifical and medical bands. Radio bands defined by the ITU-R in 5.150of the Radio Regulations and share with license-free, erro-tolerant communications applications such as wireless LANs and Bluetooth.

Bluetooth:
Wireless industry standard that uses an unlicensed radio frequency for short-range communication enabling portable devices to communicate over chort distances.

WLAN:
wireless local area network. Two or more computers or devices equipped to use spread-spectyrum technology based on radio waves for communication within a limited area.

encryption:
The application of the specific algorithm so as to alter the appearence of the data making it incomprehensive to those who are not authorized to see the information.

authentication:
Aprocess implemeted on a netwotk to verify the identify of a user.

troughput:
The rate at which a computer or network sends or receives data meassured in bits per second(bps).

wireless client:
Any host device that can connect to a wireless network.

STA:
Abbreviation for STAtion, a basic network device.

SSID:
service set identifier. The code assigned to a packet that designates that the communication is part of a wireless network.

IBSS:
independent basic service set. an 802.11 network comprised of a collection os stations that communicate with each other, but not with a network infrastructure.

BSS:
basic service set. A group of 802.11 devices connected to an access point.

ESS:
extended service set. A colection of BSSs that communicate with one another through the distribution system (usually the wired Ethernet port on an access point).

CSMA/CA:
carrier sense multiple access with collision avoidance.The basic medium access for 802.11 wireless network.

RTS:
request to send. Along with clear to send, is used by the 802.11 wireless networking protocl to reduce frame collision introduced by hidden terminal problem and exposed node problem.

CTS:
clear to send.Along with request to send, is used by the 802.11 wireless networking protocol to reduce frame collisions introduced by the hidden terminal problem and exposed node problem.

ACK:
Acknowledgement. A transmission control character(or a transmission frame) that confirms a transmitted message was received un corrupted without errors or that receiving station is ready to accept transmissions.

MAC filtering:
Access control method that permits and denies network access based on MAC addresses ti specific devices through the use of blacklists and whitelists.

open aithentication:
A type of wireless authentication where any and all clients are able to associate regardless of who they are.

PSK:
pre-shared key. A secret shared between the wireless AP and a client to control access on a network.

EAP:
Extends Authentication Protocol. An authentication framework, not a specific autjentiction mechanism. Most commonly used in wireless LANs, EAP provides common functions and a negociation of the desired authentication mechanism.

RADIUS:
remote authentication dial in user service.An AAA(authentication, authorization, and accounting) protocol used for security applications, such as network access or IP mobility. It authenticates users and machines in both local and remote aituations.

WEP:
Wired Equivalent Privacy. Part of the IEEE 802.11 wireless networking standard that provides a low level of security.

WPA: Wi-Fi Protected Access. Developed to adress security issues in WEP. Provides higher level of security in a wireless network.

firmware:
Software embedded in a hardware device typically provided on flash ROMs or as a binary image file that can be uploaded onto existing hardware by a user.

site survey:
Software installed servers and desktop computers that provides threat protection capabilities.

DIFERENT STANDRDS

802.11a
Uses 5 GHz RF spectrum
Not compatible with 2.4 GHz spectrum, i.e. 802.11 b/g/n devices
Range is approximately 33% that of the 802.11 b/g
Relatively expensive to implement compared to other technologies
Increasingly difficult to find 802.11a compliant equipment

802.11b
First of the 2.4 GHz technologies
Maximum data-rate of 11 Mbps
Range of approximately 46 m (150 ft) indoors/96 m (300 ft) outdoors

802.11g
2.4 GHz technologies
Maximum data-rate increase to 54 Mbps
Same range as the 802.11b
Backwards compatible with 802.11b

802.11n
Newest standard in development
2.4 GHz technologies (draft standard specifies support for 5 GHz)
Extends the range and data throughput
Backwards compatible with existing 802.11g and 802.11b equipment (draft standard specifies 802.11a support)

ANTENNAS:

Used on APs and Wireless bridges
Increases the output signal strength from a wireless device
Receives wireless signals from other devices such as STAs
Increase in signal strength from an antenna is known as the gain
Higher gains usually translate into increased transmission distances.

CLIENT:
also known as a STA
a mobile device that can participate in the wireless LAN

AP:
converts Ethernet Frame type to 802.11 format
controls acces by wireless clients into the wired LAN.

BRIDGE:
allows range wireless communication.