SAM HARRIS TECH REVISION

1.4 Network Security (OCR J277)

1.4.1 Threats to Computer Systems and Networks

• Malware: Malicious software including viruses, worms, Trojans, ransomware, and spyware.
• Social Engineering: Exploiting human psychology (e.g., Phishing, Shoulder surfing).
• Brute-force Attacks: Attempting every possible password combination until access is granted.
• Denial of Service (DoS): Flooding a network with traffic to crash it.
• Data Interception: Using packet sniffers to steal data during transmission.
• SQL Injection: Inserting malicious code into web forms to manipulate databases.

1.4.2 Identifying and Preventing Vulnerabilities

• Penetration Testing: Simulating attacks to find security weaknesses.
• Anti-malware Software: Tools to detect and remove malicious code.
• Firewalls: Monitoring and filtering incoming/outgoing network traffic.
• User Access Levels: Restricting data access based on a user's role.
• Passwords: Using complex strings to prevent unauthorised access.
• Encryption: Scrambling data so it cannot be read without a key.
• Physical Security: Using locks, cameras, and biometrics to protect hardware.

Related Past Paper Questions

• Year: 2023
  Explain how a firewall helps to protect a network from unauthorized access.
  Mark: [2]
• Year: 2023
  Identify two different types of physical security that can be used to protect a network.
  Mark: [2]
• Year: 2022
  Describe what is meant by 'Social Engineering'.
  Mark: [2]
• Year: 2022
  State the purpose of 'Penetration Testing' within a network security policy.
  Mark: [2]
• Year: 2021
  Explain how the use of 'Anti-malware' software can protect a computer system.
  Mark: [3]
• Year: 2021
  Define the term 'Brute-force attack'.
  Mark: [2]
• Year: 2020
  Describe the method of 'Phishing' and how a user may be able to spot it.
  Mark: [3]
• Year: 2020
  Explain the difference between 'Data Interception' and 'SQL Injection'.
  Mark: [4]
• Year: Sample Paper
  Identify two ways to prevent a 'Denial of Service (DoS)' attack.
  Mark: [2]
• Year: Sample Paper
  State why 'Encryption' is needed when transmitting data over a wireless network.
  Mark: [2]