Digital Communication Security

Question 1

Define the term virus.

Answer 1

A virus is a computer program designed to damage some aspect of an information system

Question 2

List three methods of protecting information systems from misuse.

Answer 2

1. Virus protection
2. Firewalls
3. Backups

Question 3

List three types of virus.

Answer 3

1. Worms
2. Trojan horses
3. Spyware

Question 4

Explain how worms work.

Answer 4

Worms spread by replication.
They don’t have to be attached to a file.
They slow down processing speed as they reproduce.

Question 5

Explain how trojan horses work.

Answer 5

Trojan horses provide an entry point into a computer system for hackers by misleading the user into thinking that they are downloading a useful program.

Question 6

Explain how spyware works.

Answer 6

Spyware is malicious software secretly installed on a computer.
It collects personal user information over a period of time without the user’s knowledge or consent.

Question 7

Explain how virus protection systems work.

Answer 7

They scan the computer for threats.

If the computer contains a virus, the user will be notified.

Question 8

Explain how firewalls work.

Answer 8

1. Firewalls monitor and control incoming and outgoing traffic on a network
2. They can prevent hackers, viruses and spam from entering the network via the internet
3. They can prevent users within the network from uploading to the internet

Question 9

Explain how a backup works.

Answer 9

Backups ensure that there is a copy of the data that can be loaded on to the system if the original is lost.

Question 10

Why should backups be carried out regularly?

Answer 10

To minimise the amount of data lost.

Question 11

Name two places where data can be backed up to.

Answer 11

1. Magnetic tape

2. External hard disk

Question 12

Give three advantages of Wi-Fi

Answer 12

1. No wires
2. Wide range of devices use it
3. Prices are falling

Question 13

Give three disadvantages of Wi-Fi

Answer 13

1. Signal strength decreases with distance
2. Not as secure as wired
3. Affected by the weather

Question 14

Give three advantages of 3G

Answer 14

1. Remains available if broadband is not
2. Map and GPS are still available
3. Video calling is still possible

Question 15

Give three disadvantages of 3G

Answer 15

1. Network coverage is required
2. Can be expensive
3. Causes increased power consumption

Question 16

Give three advantages of Bluetooth

Answer 16

1. Can penetrate solid objects
2. Uses less power and money
3. Can allow use of wireless headsets with phones

Question 17

Give three disadvantages of Bluetooth

Answer 17

1. Short range
2. Low security
3. Lower data transmission rate than Wi-Fi or 3G