1.3-1.4 Topologies, networks, and security

Question 1

What is an advantage of computer networks?

Answer 1

Share hardware resources like printers

Question 2

What is a disadvantage of computer networks?

Answer 2

Additional hardware is needed to set up network, can be expensive

Question 3

What are the two types of networks?

Answer 3

LAN
WAN

Question 4

What is the difference between a LAN and WAN?

Answer 4

LAN - small geographical area. Hardware is usually owned and maintained by organisation that use it.
WAN - wide geographical area. Connections are usually hired from telecommunication company

Question 5

What is a router?

Answer 5

Connects different networks together, most common is LAN to internet

Question 6

Factors which affect the performance of a network? 4

Answer 6

Bandwidth
Number of users
Error rate
Transmission media

Question 7

What is error rate?

Answer 7

Data packets colliding

Question 8

What is bandwidth?

Answer 8

Amount of data transmitted in a period of time

Question 9

How does number of users mean performance slows?

Answer 9

Large users, congestion, data packets queued before transmitted - bandwidth is shared across users

Question 10

What is transmission media?

Answer 10

Wired, wireless, how fast the cables are

Question 11

What does a switch do?

Answer 11

Allows multiple devices to be connected together

Question 12

Advantages and disadvantages of client-server model?

Answer 12

AD- Activities can be controlled by server. Updates can be done by the server
DISAD- If server is unavailable, users cannot access files, server hardware is more expensive, malware only need to attack server to gain access to all

Question 13

How does the peer to peer model work?

Answer 13

Connect all the computers to each other

Question 14

Advantages and disadvantages of peer to peer model?

Answer 14

Easy to set up as cheap, if one device fails the rest work. DISAD, Updates have to be carried out individually

Question 15

What does the domain name server do?

Answer 15

Connects each domain name ( name of website) to their IP adress

Question 16

Advantages and disadvantages of wired and wireless networks?

Answer 16

Wired - AD-Faster speed, more reliable, DISAD-Expensive, hastle to put up.
Wireless - AD, No cables(more space), easy to add new device, DISAD, less secure, shorter range

Question 17

What are the two types of topologies?

Answer 17

Star
Mesh

Question 18

Explain star topology

Answer 18

Each computer/ client is connected to a switch/central point

Question 19

Advantages and disadvantages of star topology

Answer 19

AD-secure, easy to add new devices, if one client fails doesnt affect rest.
DISAD- lots of cables, expensive, if central point fails whole thing fails

Question 20

Explain mesh topology

Answer 20

All devices are connected, either indirectly or directly

Question 21

Advantages and disadvantages of mesh topology

Answer 21

AD - if one client fails it doesnt affect rest,
DISAD - very expensive, a lot of maintainence ( for wired mesh)

Question 22

What is the definition of malware?

Answer 22

Any kind of malicious software that is installed on a computer system with intent to cause damage

Question 23

What are the 7 threats to a network?

Answer 23

Malware
Phishing
Brute force attack
Denial of service attack
Data interception
SQL injection
People as a weak point

Question 24

What is phishing?

Answer 24

An online fraud technique designed to trick computer users into giving away personal information. Disguise themselves as a trusted company

Question 25

What is brute force attack?

Answer 25

A trial-and-error method used via a computer program to decode encrypted data like passwords

Question 26

What is Denial of service?

Answer 26

Flooding a server with useless traffic, causing it to become overloaded and unavailable.

Question 27

What is data interception?

Answer 27

Monitoring data streams to and from a target to gather sensitive information.

Question 28

What is SQL injection?

Answer 28

A code injection technique used to attack data-driven applications. Code can be entered into text boxes and is then executed by the server.

Question 29

What is people as a weak point?

Answer 29

Not installing updates Not locking doors Sharing passwords Not encrypting data Not logging off

Question 30

What does malware cover?

Answer 30

Viruses Trojans Ransomware Spyware Adware

Question 31

Explain Viruses and worms

Answer 31

Viruses code is only run when host program is executed. Worms do not need to be hosted. Self replicating

Question 32

Explain Trojans and ransomware

Answer 32

Trojans are programs which seen legitimate but arnt. Ransomware interfers with computer operation unless a sum of money is paid

Question 33

What is spyware?

Answer 33

Spyware gathers information and sends it to the criminal, like key strokes to obtain password.

Question 34

How can you prevent malware?

Answer 34

Install anti-virus and anti-spy software. Implement user access levels Educate users about the risks of opening unknown sources

Question 35

How can you prevent people being a weak point?

Answer 35

Educate users so they are aware of criminal tactics. Ensure network and security polices are followed

Question 36

How can you prevent brute force attacks?

Answer 36

Use long passwords Limit amount of password attempts allowed Use two factor authentication

Question 37

How can you prevent denial of service attacks?

Answer 37

Install firewall to reject packets Configure a firewall to restrict number of packets allowed in a time frame

Question 38

How can you prevent SQL injection?

Answer 38

Input sanitation - removing special characters and SQL commands from input before processing it Dont permit certain characters

Question 39

How can you prevent data interception and theft?

Answer 39

Strong encryption Ensure websites use HTTPS connections Do not use unencrypted free wifi