Networks and cyber security flashcards

Networks and cyber security covers how computers are connected and how data is kept safe. Students must understand the types of networks (LAN and WAN), how devices communicate using protocols and the TCP/IP model, and the roles of hardware such as routers, switches and network interface cards. Wired and wireless transmission methods are compared, including their advantages and limitations. Students also need to understand network topologies such as star and mesh. On the security side, students must know common cyber threats including malware, phishing and denial of service attacks, as well as protective measures such as firewalls, encryption, strong passwords and two-factor authentication. Understanding why networks are vulnerable and how organisations defend against attacks is essential for the exam.

1. Card 1

   What is the difference between a LAN and a WAN?

   A LAN (Local Area Network) covers a small area like a school. A WAN (Wide Area Network) spans large geographical areas, such as the internet.

2. Card 2

   What does a router do in a network?

   A router directs data packets between different networks, choosing the best path for data to travel from source to destination.

3. Card 3

   What is a network protocol?

   A protocol is an agreed set of rules that controls how devices communicate across a network, ensuring data is sent and received correctly.

4. Card 4

   What are the four layers of the TCP/IP model?

   The TCP/IP model has four layers: Application, Transport, Internet, and Network Access (Link). Each layer handles a different part of data transmission.

5. Card 5

   What is the difference between a star topology and a mesh topology?

   In a star topology all devices connect to a central switch. In a mesh topology devices connect directly to each other, providing multiple paths for data.

6. Card 6

   What is malware?

   Malware is malicious software designed to damage, disrupt or gain unauthorised access to a computer system. Examples include viruses, ransomware and spyware.

7. Card 7

   What is a phishing attack?

   Phishing is a social engineering attack where criminals send fake emails or messages to trick users into revealing sensitive information such as passwords.

8. Card 8

   What is a denial of service (DoS) attack?

   A denial of service attack floods a server with requests, overwhelming it so that legitimate users cannot access the service or website.

9. Card 9

   How does encryption protect data on a network?

   Encryption scrambles data into unreadable ciphertext using a key, so that even if data is intercepted, it cannot be understood without the correct decryption key.

10. Card 10

    What is a firewall and what does it do?

    A firewall monitors incoming and outgoing network traffic and blocks data packets that do not meet defined security rules, protecting against unauthorised access.

11. Card 11

    What is two-factor authentication (2FA)?

    Two-factor authentication requires users to verify identity in two ways, such as a password plus a one-time code, making unauthorised access much harder.

12. Card 12

    What is the difference between a switch and a hub?

    A switch sends data only to the intended device on a network. A hub broadcasts data to all connected devices, which is less efficient and less secure.

• Many students confuse a switch with a router, but a switch connects devices within the same network whilst a router connects different networks together.
• Students often think encryption prevents data from being intercepted, when in fact it only makes intercepted data unreadable without the correct key.
• A common error is describing a firewall as antivirus software, but a firewall controls network traffic based on rules whereas antivirus software detects and removes malicious programs already on a device.

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