Question 1: Define the term 'phishing' and explain how it can threaten network security.

Answer: Phishing is a cyber attack where attackers send deceptive emails or messages that appear legitimate to trick individuals into revealing sensitive information, such as passwords or bank details, thereby compromising network security.

Question 2: List three common types of malware that can infect computer networks.

Answer: The three common types of malware are viruses, worms, and ransomware.

Question 3: Describe the purpose of a firewall in network security.

Answer: A firewall acts as a barrier that monitors and filters incoming and outgoing network traffic based on security rules, helping to prevent unauthorised access to a network.

Question 4: Explain what a Denial of Service (DoS) attack is and how it affects a network.

Answer: A DoS attack floods a network or server with excessive traffic, overwhelming its resources and making it unavailable to legitimate users.

Question 5: Complete the following truth table for an AND gate:

Answer: Input A | Input B | Output 0 | 0 | 0 0 | 1 | 0 1 | 0 | 0 1 | 1 | 1

Question 6: Draw a logic circuit for an OR gate using basic logic gate symbols. Label all parts clearly.

Answer: A correct sketch would include two input lines entering an OR gate symbol (curved shape), with one output line exiting the gate. The inputs are typically labeled A and B, and the output labeled as A OR B.

Question 7: Identify and explain two ways to protect a network against malware infections.

Answer: Two ways to protect a network against malware are: 1) Installing and regularly updating antivirus software to detect and remove malware; 2) Implementing user training to recognise suspicious emails and links to prevent accidental downloads.

Question 8: Describe what a VPN (Virtual Private Network) does to enhance network security.

Answer: A VPN creates a secure, encrypted connection over the internet between a user’s device and a network, protecting data from eavesdropping and allowing safe remote access.

Question 9: Sketch a simple diagram of a network with a secure Wi-Fi router connected to multiple devices and a firewall protecting the network. Leave space for the drawing.

Answer: A correct sketch would show a central Wi-Fi router connected via lines to several devices (such as laptops, smartphones). The router should be protected by a firewall symbol placed between the internet connection and the network devices.

Question 10: Explain the role of encryption in safeguarding data transmitted over a network.

Answer: Encryption converts data into a coded form that can only be read by someone with the correct decryption key, ensuring that sensitive information remains confidential during transmission.

Question 11: List two methods that network administrators can use to detect suspicious or malicious activity on a network.

Answer: Methods include monitoring network traffic using Intrusion Detection Systems (IDS) and analysing logs for unusual activity or access patterns.