communication, network, and cyber threats

Question 1

• Modem

Answer 1

Modems modulate (convert) a computer’s digital data to analog data, transmit it, then demodulate (reconvert) it back to digital data for the receiving computer.

Question 2

Network:

Answer 2

system of interconnected computers, telephones,

and/or other communications devices that can communicate with one another and share applications and data.

Question 3

Benefits of Networks

Answer 3

Share peripheral devices, such as printers, scanners, disk drives
• Share software
• Share data and information
• Better communications
• Accessing databases

Question 4

Wide area network (WAN):

Answer 4

Communications network that covers a wide
geographic area, such as a country or the world. Most long-distance and regional telephone companies are WANs. the internet is a WAN

Question 5

Metropolitan area network (MAN):

Answer 5

Communications network covering a

city or a suburb. Many cellphone systems are MANs.

Question 6

Local area network (LAN):

Answer 6

Connects computers and devices in a limited

geographic area, such as one office, one building, or a group of buildings close together.

Question 7

How Networks Are Structured

Client/Server

Answer 7

Consists of clients, which are computers that request data, and servers, which are computers that supply data.

Question 8

How Networks Are Structured

Peer-to-Peer (P2P)

Answer 8

All computers on the network are “equal” and communicate directly with one another, without relying on servers.

Question 9

Intranets

Answer 9

—use infrastructure and standards of the Internet and the web, but for an organization’s internal use only.

Question 10

Extranets

Answer 10

similar to intranets but allows use by selected outside

entities, such as suppliers.

Question 11

VPNs

Answer 11

use a public network (usually the Internet) plus intranets and extranets to connect an organization’s various sites) but on a private basis, via encryption and authentication

Question 12

wired

Answer 12

twisted-pair, coaxial cable, fiber-optic cable

Question 13

wireless

Answer 13

infrared, microwave, radio, Wi-Fi, satellite

Question 14

Hosts and Nodes

Answer 14

Client/server network has a host computer, which

controls the network; a node is any device attached to the network

Question 15

Packets

Answer 15

fixed-length blocks of data for transmission, reassembled after transmission

Question 16

Protocols

Answer 16

set of conventions, or rules, governing the exchange of data between hardware and/or software components in the network; built into the hardware or software you are using.

Question 17

Each packet, or electronic message, carries four types of information that will help it get to its destination

Answer 17

1. the sender’s address (IP)
2. the intended receiver’s address
3. how many packets the complete message has been broken into
4. the number of this particular packet. The packets carry the data in the protocols that the Internet uses—that is, TCP/IP

Question 18

Network linking devices:

Answer 18

Switch—Device that connects computers to a network; sends only to intended recipients; operates back and forth at the same time.
• Bridge—Interface device that connects same type of networks.
• Gateway—Interface device that connects dissimilar networks.
• Router—Device that directs messages among several networks, wired or and/or wireless.
• Backbone—Main Internet highway that connects all networks in an organization; includes switches, gateways, routers, etc.
• NIC (Network interface card)—inserted in a slot on the motherboard, enables computer to operate as part of a network.
• NOS (network operating system)—the system software that manages network activity.

Question 19

Network topology: The layout (shape) of a network

Answer 19

• Star – all nodes are connected through a central network switch
• Ring – all nodes are connected in a continuous loop
• Bus – all nodes are connected to a single wire or cable
• Tree – a bus network of star networks
• Mesh – messages sent to the destination can take any possible shortest, easiest route to reach its destination.

Question 20

Ethernet

Answer 20

Network standard for linking all devices in a local area network that describes how data can be sent between computers and other networked devices usually in close proximity.

Question 21

Communications media

Answer 21

are the means of interchanging or transmitting and receiving information.

Question 22

Twisted-Pair Wire (dial-up connections)

Answer 22

slow

Question 23

Coaxial Cable

Answer 23

Used for cable TV and cable Internet electric signals

Question 24

Fiber-optic cable

Answer 24

Dozens or hundreds of thin strands of glass or plastic that transmit pulses of light, not electricity
• Can transmit up to 2 gigabits per second (very fast)

Question 25

Bandwidth:

Answer 25

range (band) of frequencies that a transmission

medium can carry in a given period of time

Question 26

narrowband / broad band

Answer 26

narrow band doesn’t have much

broad band has a lot

Question 27

WAP (wireless application protocol):

Answer 27

Wireless handheld devices such as cellphones use the Wireless Application Protocol for connecting wireless users to the Web.

Question 28

Five Types of Wireless Communications Media

Answer 28

Infrared transmission (wireless remote)
Broadcast radio(sends data long distances, transmitter and receiver)
Cellular radio(used in cellphones and wireless modems)
Microwave radio( telephones)
Communication satellites (basis for gps)

Question 29

communication satellites can be placed at different elevations GEO,MEO, LEO,

Answer 29

GEO - highest 22000 miles
MEO - 5000 - 10000 miles
LEO - 200-1000 miles

Question 30

Long-Distance Wireless: One-Way Communication

Answer 30

One-way Pagers:

Question 31

Long-Distance Wireless: Two-Way Communication

Answer 31

1G
2G
3G
4G
LTE

Question 32

Short-Range Wireless: Two-Way Communication

Answer 32

Local Area Networks (wifi)
Personal Area Networks (bluetooth)
Home Automation networks(zigbee)

Question 33

• Denial of Service Attack

Answer 33

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

Question 34

Virus

Answer 34

Deviant program that hides in a file or a program on a disk, flash memory drive, in an e-mail, or in a web link and that causes unexpected effects such as destroying or corrupting data

Question 35

Worms

Answer 35

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

Question 36

Trojan Horses

Answer 36

Programs that pretend to be a useful program such as a free game or a screensaver but that carry viruses or malicious instructions that damage your computer or install a backdoor or spyware.

Question 37

Rootkits

Answer 37

In many computer operating systems, the “root” is an account for system administration. A “kit” is the malware secretly introduced into the computer. A rootkit gives an attacker “super powers” over computers—for example, the ability to steal sensitive personal information.

Question 38

blended threats

Answer 38

A blended threat is a more sophisticated attack that bundles some of the worst aspects of viruses, worms, Trojan horses, and other malware into one single threat.

Question 39

Zombies & Bots

Answer 39

A botmaster uses malware to hijack hundreds to many thousands of computers and is able to remotely control them all, including the ability to update the malware and to introduce other programs such as spyware. Hijacked computers are called zombies.

•A botnet (robot network) is a network of computers in which each computer has been implanted with instructions to wait for commands from the person controlling the botnet.

Question 40

Ransomeware

Answer 40

A botnet may be used to install ransomeware, which holds the data on a computer or the use of the computer hostage until a payment is made. Ransomware encrypts the target’s files, and the attacker tells the victim to make a payment of a specified amount to a special account to receive the decryption key.

Question 41

Time, Logic, & Email Bombs:

Answer 41

A time bomb is malware programmed to “go
off” at a particular time or date.
A logic bomb is “detonated” when a specific event occurs—for example, all personnel records are erased when an electronic notation is made that a particular person was fired.
Email bombs overwhelm a person’s email account by surreptitiously subscribing it to dozens or even hundreds of mailing lists.

Question 42

Phone Malware:

Answer 42

Worms and viruses and other malware are attacking
smartphones. The most common type of cellphone infection occurs when a cellphone downloads an infected file from a PC or the Internet, but phone-to-phone viruses are also on the rise.

Question 43

Cyberthreats

• How they spread

Answer 43

• Via e-mail attachments
• By infected disks and flash drives
• By clicking on infiltrated websites
• By downloading infected files from websites
• Through infiltrated Wi-Fi hotspots
• From one infected PC on a LAN to another

Question 44

Encryption

Answer 44

Process of altering readable data into unreadable form to prevent unauthorized access

Question 45

Some threats to privacy:

Answer 45

• Name migration
• Résumé rustling & online snooping
• Government prying & spying

Question 46

Identity (ID) theft, or theft of identity (TOI),

Answer 46

is a crime in which thieves hijack your name and identity and use your information and credit rating to get cash or buy things.
• Wallet or purse theft
• Mail theft
• Mining the trash
• Telephone solicitation
• Insider access to database
• Outsider access to database