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Networking, Security and Cloud questions

OSI, TCP/IP, protocols, security threats and cloud models.

1. How many layers does the OSI model have?

  1. 5
  2. 6
  3. 7
  4. 4
Answer

C. 7 Physical, Data Link, Network, Transport, Session, Presentation, Application.

2. Which layer of the OSI model handles routing between networks?

  1. Network layer
  2. Data link layer
  3. Transport layer
  4. Session layer
Answer

A. Network layer IP addressing and routing are at layer 3.

3. TCP differs from UDP because TCP is:

  1. Used only for video
  2. Faster with no acknowledgements
  3. Connection-oriented and reliable
  4. A physical layer protocol
Answer

C. Connection-oriented and reliable TCP guarantees ordered delivery; UDP does not.

4. What does DNS do?

  1. Assigns MAC addresses
  2. Stores emails
  3. Translates domain names into IP addresses
  4. Encrypts web pages
Answer

C. Translates domain names into IP addresses DNS resolves names like example.com to IPs.

5. Which protocol automatically assigns IP addresses to devices on a network?

  1. DNS
  2. SMTP
  3. FTP
  4. DHCP
Answer

D. DHCP Dynamic Host Configuration Protocol.

6. The default port for HTTPS is:

  1. 80
  2. 21
  3. 25
  4. 443
Answer

D. 443 HTTP uses 80; HTTPS uses 443.

7. An IPv4 address is how many bits long?

  1. 32
  2. 16
  3. 128
  4. 64
Answer

A. 32 IPv6 addresses are 128 bits.

8. Which device forwards packets between different networks?

  1. Router
  2. Hub
  3. Repeater
  4. Modem only
Answer

A. Router Routers connect networks.

9. A MAC address identifies:

  1. An email account
  2. A website
  3. A network interface card
  4. A domain
Answer

C. A network interface card MAC addresses are hardware addresses.

10. Which protocol is used to send email?

  1. FTP
  2. HTTP
  3. SNMP
  4. SMTP
Answer

D. SMTP Simple Mail Transfer Protocol.

11. Phishing is:

  1. A network cable
  2. A type of firewall
  3. Tricking people into revealing information through fake messages or sites
  4. A backup method
Answer

C. Tricking people into revealing information through fake messages or sites Phishing imitates trusted senders.

12. A firewall is used to:

  1. Speed up the internet
  2. Filter network traffic based on security rules
  3. Cool the server
  4. Store passwords
Answer

B. Filter network traffic based on security rules Firewalls allow or block traffic.

13. Which is an example of two-factor authentication?

  1. A long password
  2. A username and email
  3. A password plus a one-time code sent to your phone
  4. Two passwords
Answer

C. A password plus a one-time code sent to your phone Two different factors: something you know and something you have.

14. Encryption converts data into:

  1. A database table
  2. A smaller file
  3. A form that only authorised parties can read
  4. Plain text
Answer

C. A form that only authorised parties can read Encrypted data needs a key to read.

15. Malware that encrypts files and demands payment is called:

  1. Adware
  2. Ransomware
  3. Spyware
  4. Firmware
Answer

B. Ransomware Ransomware holds data hostage.

16. A DDoS attack aims to:

  1. Steal a password silently
  2. Fix software bugs
  3. Overwhelm a service with traffic so it becomes unavailable
  4. Encrypt a hard drive
Answer

C. Overwhelm a service with traffic so it becomes unavailable Distributed Denial of Service floods a target.

17. SQL injection happens when:

  1. A database is backed up
  2. Untrusted input is inserted into a database query without proper handling
  3. Too many users log in
  4. A table has no index
Answer

B. Untrusted input is inserted into a database query without proper handling Parameterised queries prevent it.

18. HTTPS is more secure than HTTP because it:

  1. Removes cookies
  2. Stores pages offline
  3. Uses a faster port
  4. Encrypts data in transit using TLS
Answer

D. Encrypts data in transit using TLS TLS protects data between browser and server.

19. Cloud computing means:

  1. Weather prediction software
  2. Storing data on a pen drive
  3. Using only local servers
  4. Using computing resources such as servers and storage over the internet on demand
Answer

D. Using computing resources such as servers and storage over the internet on demand Resources are rented as services.

20. IaaS, PaaS and SaaS are:

  1. Database types
  2. Programming languages
  3. Cloud service models
  4. Network cables
Answer

C. Cloud service models Infrastructure, Platform and Software as a Service.

21. Gmail is an example of:

  1. SaaS
  2. PaaS
  3. IaaS
  4. On-premise software
Answer

A. SaaS Users use the software directly over the internet.

22. Renting virtual machines from a provider such as AWS EC2 is an example of:

  1. SaaS
  2. PaaS
  3. IaaS
  4. FaaS only
Answer

C. IaaS You manage the OS; the provider runs the hardware.

23. Which is a benefit of cloud computing?

  1. Unlimited free storage
  2. Scaling resources up or down as needed
  3. No internet needed
  4. No security needed
Answer

B. Scaling resources up or down as needed Elastic scaling is a key benefit.

24. A public cloud is:

  1. A government website
  2. A server in your own office only
  3. Shared infrastructure offered by a provider to many customers
  4. A free Wi-Fi network
Answer

C. Shared infrastructure offered by a provider to many customers Examples include AWS, Azure and Google Cloud.

25. Serverless computing (e.g. AWS Lambda) means:

  1. Code runs only on your laptop
  2. You run code without managing servers; the provider handles scaling
  3. There are no servers anywhere
  4. Servers are shut down
Answer

B. You run code without managing servers; the provider handles scaling Servers exist but are fully managed.

26. A VPN mainly provides:

  1. An encrypted connection over a public network
  2. Faster downloads
  3. Antivirus scanning
  4. Free storage
Answer

A. An encrypted connection over a public network Virtual Private Network.

27. Which protocol transfers files between client and server?

  1. FTP
  2. ARP
  3. SMTP
  4. DHCP
Answer

A. FTP File Transfer Protocol.

28. Which network topology connects every device to a central hub or switch?

  1. Mesh
  2. Bus
  3. Star
  4. Ring
Answer

C. Star Star topology has a central device.

29. What does a subnet mask do?

  1. Encrypts traffic
  2. Separates the network part of an IP address from the host part
  3. Hides the IP address
  4. Assigns domain names
Answer

B. Separates the network part of an IP address from the host part It defines which bits identify the network.

30. Which of these is a strong password practice?

  1. Write it on your monitor
  2. Use your birth date
  3. Use a long, unique password for each account
  4. Reuse one password everywhere
Answer

C. Use a long, unique password for each account Unique long passwords limit the damage of leaks.

31. How many layers does the OSI model have?

  1. 5
  2. 7
  3. 4
  4. 6
Answer

B. 7 Physical, data link, network, transport, session, presentation, application.

32. Which OSI layer is responsible for routing packets between networks?

  1. Network layer
  2. Data link layer
  3. Session layer
  4. Transport layer
Answer

A. Network layer Routers work at the network layer (layer 3).

33. Which protocol is connection-oriented and guarantees delivery?

  1. IP
  2. UDP
  3. TCP
  4. ICMP
Answer

C. TCP TCP uses acknowledgements and retransmission.

34. Which protocol is used for video calls where speed matters more than perfect delivery?

  1. UDP
  2. SMTP
  3. TCP
  4. FTP
Answer

A. UDP UDP has low overhead and no retransmission delay.

35. DNS is used to:

  1. Encrypt emails
  2. Compress files
  3. Assign MAC addresses
  4. Translate domain names into IP addresses
Answer

D. Translate domain names into IP addresses DNS works like the internet's phone book.

36. Which protocol automatically assigns IP addresses to devices on a network?

  1. DNS
  2. ARP
  3. SMTP
  4. DHCP
Answer

D. DHCP DHCP leases addresses to clients.

37. What is the default port for HTTPS?

  1. 25
  2. 443
  3. 80
  4. 21
Answer

B. 443 HTTP uses 80; HTTPS uses 443.

38. ARP maps:

  1. Ports to services
  2. Domain names to IP addresses
  3. MAC addresses to domain names
  4. IP addresses to MAC addresses
Answer

D. IP addresses to MAC addresses ARP finds the hardware address for a known IP.

39. How many bits are in an IPv4 address?

  1. 64
  2. 128
  3. 16
  4. 32
Answer

D. 32 IPv4 is 32 bits; IPv6 is 128 bits.

40. Which device connects different networks and forwards packets by IP address?

  1. Modem only
  2. Hub
  3. Repeater
  4. Router
Answer

D. Router Routers choose paths between networks.

41. A firewall is used to:

  1. Speed up the internet
  2. Filter network traffic based on rules
  3. Store backups
  4. Assign IP addresses
Answer

B. Filter network traffic based on rules It allows or blocks traffic.

42. An email pretending to be from your bank asking for your password is an example of:

  1. Load balancing
  2. Encryption
  3. Phishing
  4. Firewall
Answer

C. Phishing Phishing tricks users into revealing secrets.

43. Encryption that uses the same key to encrypt and decrypt is called:

  1. Symmetric encryption
  2. Asymmetric encryption
  3. Hashing
  4. Encoding
Answer

A. Symmetric encryption AES is a common symmetric cipher.

44. Which of these is a hashing algorithm?

  1. RSA
  2. SHA-256
  3. AES
  4. TLS
Answer

B. SHA-256 SHA-256 produces a fixed-size digest and cannot be reversed.

45. Two-factor authentication requires:

  1. Two usernames
  2. Two passwords
  3. Two different types of proof, such as a password and an OTP
  4. Logging in twice
Answer

C. Two different types of proof, such as a password and an OTP It combines something you know with something you have or are.

46. A DDoS attack aims to:

  1. Make a service unavailable by flooding it with traffic
  2. Encrypt files for ransom
  3. Steal passwords by guessing
  4. Read emails
Answer

A. Make a service unavailable by flooding it with traffic Many machines overwhelm a target.

47. In cloud computing, SaaS means:

  1. Server as a System
  2. Software as a Service
  3. Storage as a Service
  4. Security as a Service
Answer

B. Software as a Service Example: Gmail, used through a browser.

48. Which cloud model gives you virtual machines, storage and networks to manage yourself?

  1. SaaS
  2. IaaS
  3. FaaS only
  4. PaaS
Answer

B. IaaS Infrastructure as a Service, e.g. AWS EC2.

49. A cloud owned by one organisation for its own use is a:

  1. Hybrid cloud
  2. Community cloud
  3. Private cloud
  4. Public cloud
Answer

C. Private cloud Public clouds are shared; private clouds serve one organisation.

50. Automatically adding servers when traffic rises is called:

  1. Compression
  2. Caching
  3. Virtualisation
  4. Auto-scaling
Answer

D. Auto-scaling Auto-scaling adjusts capacity to demand.

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