CS - Comp Systems - Security

Question 1

Describe the purpose of a firewall

Answer 1

A firewall can be used to:

• check that incoming data packets meet specific rules before being allowed in
• set rules about which stations on a network can send or receive data packets

Question 2

What threats do firewalls protect against?

Answer 2

Firewalls protect against unauthorised access to a computer system by those who might want to steal data, cause malicious harm or take control of the system.

Question 3

What is encryption?

Answer 3

A security measure used to prevent unauthorised access to data during transmission between systems or networks.

Question 4

Describe the purpose of encryption

Answer 4

Designed to scramble data so if an unauthorised person or organisation manage to steal data packets, they will be unable to understand the content.

Question 5

Describe the process of encryption

Answer 5

In computing, encryption:

• makes use of algorithms to create simple keys that can encrypt data
• keeps the simple key secure by using public and private keys during transmission of data
• only the correct combination of public and private key will allow access to the simple key
• the simple key is then used again to decrypt the data

Question 6

Describe the use of the public and private key when a message is received

Answer 6

When a message is received, the public key used to send the data must be recognised as the key that corresponds to the private key used to receive the data.