Chapter Four

Question 1

Wireless Access Point (AP)

Answer 1

A network device that provides connectivity of wireless clients to connect to a data network. A wireless AP uses radio waves to communicate with the wireless NICs in the devices and other wireless access points

Question 2

Network Interface Card (NIC)

Answer 2

Computer hardware, typically used for LANs, that allows a computer to connect to some networking cable. The NIC can then send and receive data over the cable at the direction of the computer

Question 3

International Organization for Standardization (ISO)

Answer 3

an international standards body that defines many networking standards and that created the OSI model

Question 4

Telecommunications Industry Association/Electronic Industries Association (TIA/EIA

Answer 4

an organization that develops standards that relate to telecommunication technologies. Together, the TIA and the Electronic Industries Alliance (EIA) have formalized standards, such as EIA/TIA-232, for the electrical characteristics of data transmission

Question 5

International Telecommunication Union (ITU)

Answer 5

– a United Nations (UN) agency responsible for issues that concern information and communication technologies

Question 6

American National Standards Institute (ANSI

Answer 6

A private nonprofit organization that oversees the development of standards in the United States

Question 7

Institute of Electrical and Electronics Engineers (IEEE)

Answer 7

an international, nonprofit organization for the advancement of technology related to electricity. IEEE maintains the standards defining many LAN protocols.

Question 8

Encoding

Answer 8

a process by which bits are represented on a medium

Question 9

Manchester Encoding

Answer 9

– use of a line code in which each bit of data is signified by at least one voltage level transition.

Question 10

Bandwidth

Answer 10

the rated throughput capacity of a given network medium or protocol. Bandwidth is listed as available or consumed data communication resources expressed in bits per second.

Question 11

Throughput

Answer 11

the actual data transfer rate between two computers at some point in time. Throughput is impacted by the slowest-speed link used to send data between the two computers, as well as myriad variables that might change during the course of a day

Question 12

Goodput

Answer 12

Application-level throughput. It is the number of useful bits per unit of time from a certain source address to a certain destination, excluding protocol overhead and excluding retransmitted data packets

Question 13

Electromagnetic Interference (EMI)

Answer 13

Interference by magnetic signals caused by the flow of electricity. EMI can cause reduced data integrity and increased error rates on transmission channels. Electrical currents create magnetic fields, which in turn cause other electrical currents in nearby wires, and the induced electrical currents can interfere with the proper operation of the other wire.

Question 14

Crosstalk

Answer 14

a source of interference that occurs when cables are bundled together for long lengths, in which the signal from one cable leaks out and enters adjacent cables

Question 15

Unshielded Twisted-Pair (UTP) Cable

Answer 15

a general type of cable, with the cable holding twisted pairs of copper wires and the cable itself having little shielding

Question 16

Shielded Twisted Pair (STP) Cable

Answer 16

a type of networking cabling that includes twisted-pair wires, with shielding around each pair of wires, as well as another shield around all wires in the cable.

Question 17

Coaxial Cable

Answer 17

Cable consisting of a hollow outer cylindrical conductor that surrounds a single inner wire conductor. Two types of coaxial cable are currently used in LANs: 50-ohm cable, which is used for digital signaling, and 75-ohm cable, which is used for analog signaling

Question 18

Fiber-Optic Cable

Answer 18

a physical medium that uses glass or plastic threads to transmit data. A fiber-optic cable consists of a bundle of these threads, each of which is capable of transmitting data into light waves

Question 19

Wi-Fi

Answer 19

a wireless LAN (WLAN) technology that uses a contention-based protocol known as CSMA/CA. The wireless NIC must first listen before transmitting to determine if the radio channel is clear. If another wireless device is transmitting, the NIC must wait until the channel is clear. Wi-Fi, which is a trademark of the Wi-Fi Alliance, is used with certified WLAN devices based on the IEEE 802.11 standards

Question 20

Bluetooth

Answer 20

a wireless personal area network (WPAN) standard that uses a device pairing process to communicate over distances from 1 to 100 meters

Question 21

WiMAX

Answer 21

Worldwide Interoperability for Microware Access, a wireless standard that uses a point-to-multipoint topology to provide wireless broadband access

Question 22

Zigbee

Answer 22

a specification used for low-data-rate, low-power communications. It is intended for applications that require short ranges, low data rates, and long battery life. Zigbee is typically used for industrial and Internet of Things (IoT) environments such as wireless light switches and medical device data collection