Wireless Data - Information Technology Quiz

Wireless Data – Information Technology Quiz

The key terms of Information Technology Quiz include, Wireless, Data, Business, Digital, Standard.

Bluetooth

a short-range wireless digital standard aimed at linking cellphones, PDAs, computers, and peripherals up to distances of about 30 feet.

ultra wideband

a promising technology operating in the range of 480 megabits per second up to about 30 feet that uses a low power source to send out millions of bursts of radio energy every second over many different frequencies, which are then reassembled by a UWB receiver.

wireless USB (WUSB)

has a typical range of 32 feet and a maximum data rate of 480 megabits per second.

denial-of-service (DoS) attacks

consists of making repeated requests of a computer system or network, thereby overloading it and denying legitimate users access to it.

worm

a program that copies itself repeatedly into a computer’s memory or into a disk drive.

virus

a “deviant” program, stored on a computer floppy disk, hard drive, or CD, that can cause unexpected and often undesirable effects, such as destroying or corrupting data.

trojan horse

a program that pretends to be a useful program, and usually free, such as a game or screen saver, but carries viruses, or destructive instructions, that perpetrate mischief without your knowledge.

hackers

1. computer enthusiasts, people who enjoy learning programming languages and computer systems, but also 2. people who gain unauthorized access to computers or networks, often just for the challenge of it.

twisted pair wire

consists of two strands of insulated copper wire, twisted around each other. This twisted-pair configuration (compared to straight wire) somewhat reduces interference (called “crosstalk”) from electrical fields.

coaxial cable (commonly called) co-ax

a high-frequency transmission cable that consists of insulated copper wire wrapped in a solid or braided metal sheild and then in an external plastic cover.

fiber-optic cable

consists of dozens or hundreds of thin strands of glass or plastic that transmit pulsating beams of light rather than electricity.

HomePNA technology

an alliance of leading technology companies working to ensure the adoption of a single, unified existing wire (telephone and cable) home-networking standard that transmits data at about 320 megabits per second.

HomePlug technology

a standard that allows users to send data over a home’s existing electrical (AC) power lines.

electromagnetic spectrum of radiation

the basis for all telecommunications signals, carried by both wire and wireless media.

radio-frequency (or) RF spectrum

fields of electrical energy and magnetic energy that carry most communications signals.

bandwidth

the range, or band, of frequencies that a transmission medium can carry in a given period of time.

narrowband

also known as voiceband, is used for regular telephone communications

broadband

the bandwidth used to transmit high-speed data and high-quality audio and video.

WAP

wireless application protocol is designed to link nearly all mobile devices to your telecommunications carrier’s wireless network and content providers.

infrared wireless transmission

sends data signals using infrared-light waves at a frequency to low (1-16 megabits per second) for human eyes to recieve and interpret.

broadcast radio

a wireless transmission medium that sends data over long distances at up to 2 megabits per second – between regions, states, or countries.

cellular radio

a medium of transmission that is widely used for cellphones and wireless modems, using high-frequency radio waves to transmit voice and digital messages.

microwave radio

a medium of transmission that transmits voice and data at 45 megabits per second through the atmosphere as super-high frequency radio waves called microwaves, which vibrate at 2.4 gigahertz (2.4 billion hertz) per second or higher.

communications satellites

microwave relay stations in orbit around the earth.

GEO

geostationary earth orbit satellites. 22,300 miles above the earth at the equator.

MEO

medium-earth orbit satellites. 5,000 to 10,000 miles above the earth’s surface.

LEO

low-earth orbit satellites. 200 to 1,000 miles up. LEO satellites have no signal delay.

GPS (global positioning system)

GPS consists of 24 to 32 MEO earth-orbiting satellites continuously transmitting timed radio signals that can be used to identify earth locations.

pagers

simple radio recievers that receive data sent from a special radio transmitter.

analog cellphones

devices designed primarily for communicating by voice through a system of ground-area cells. Each cell is hexagonal in shape, usually 8 miles or less in diameter, and is served by a transmitter receiving tower.

digital wireless services

a network which supports digital cell-phones and personal assistants – and uses a network of cell towers to send voice communications and data over the airwaves in digital form.

Wi-Fi (short for wireless fidelity)

a short-range wireless digital standard aimed at helping portable computers and handheld wireless devices to communicate at high speeds and share internet connections at distances of 100 to 280 feet.

Wi-Fi a

The 802.11a standard uses the same data link layer protocol and frame format as the original standard, but an OFDM based air interface (physical layer). It operates in the 5 GHz band with a maximum net data rate of 54 Mbit/s, plus error correction code, which yields realistic net achievable throughput in the mid-20 Mbit/s

Wi-Fi b

802.11b has a maximum raw data rate of 11 Mbit/s and uses the same media access method defined in the original standard. 802.11b products appeared on the market in early 2000, since 802.11b is a direct extension of the modulation technique defined in the original standard. The dramatic increase in throughput of 802.11b (compared to the original standard) along with simultaneous substantial price reductions led to the rapid acceptance of 802.11b as the definitive wireless LAN technology.

Wi-Fi g

In June 2003, a third modulation standard was ratified: 802.11g. This works in the 2.4 GHz band (like 802.11b), but uses the same OFDM based transmission scheme as 802.11a. It operates at a maximum physical layer bit rate of 54 Mbit/s exclusive of forward error correction codes, or about 22 Mbit/s average throughput. 802.11g hardware is fully backwards compatible with 802.11b hardware and therefore is encumbered with legacy issues that reduce throughput when compared to 802.11a by ~21%

Wi-Fi n

802.11n is an amendment which improves upon the previous 802.11 standards by adding multiple-input multiple-output antennas (MIMO). 802.11n operates on both the 2.4GHz and the lesser used 5 GHz bands. The IEEE has approved the amendment and it was published in October 2009. Prior to the final ratification, enterprises were already migrating to 802.11n networks based on the Wi-Fi Alliance’s certification of products conforming to a 2007 draft of the 802.11n proposal.