Computer Networks MCQ Test
63 Computer Networks multiple-choice questions with answers, from the PGDCA syllabus. Instant score, full answer review, free and no signup.
Each attempt picks 25 questions at random from the 63 in this topic.
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Ask about the certificateAll 63 Computer Networks questions with answers
1. What is a computer network?
- A. A single powerful computer
- B. Two or more computers connected to share data and resources
- C. A type of software
- D. An operating system
Answer: Two or more computers connected to share data and resources
2. What does LAN stand for?
- A. Long Area Network
- B. Local Area Network
- C. Linked Access Node
- D. Logical Address Number
Answer: Local Area Network
3. Which network type covers the largest geographical area?
- A. LAN
- B. MAN
- C. WAN
- D. PAN
Answer: WAN
4. What does MAN stand for in networking?
- A. Main Access Network
- B. Metropolitan Area Network
- C. Managed Area Node
- D. Multiple Access Network
Answer: Metropolitan Area Network
5. Which network covers a very small area such as around one person?
- A. LAN
- B. WAN
- C. PAN
- D. MAN
Answer: PAN
6. How many layers does the OSI reference model have?
- A. 4
- B. 5
- C. 7
- D. 9
Answer: 7
7. Which is the lowest layer of the OSI model?
- A. Data Link
- B. Physical
- C. Network
- D. Transport
Answer: Physical
8. Which is the topmost layer of the OSI model?
- A. Session
- B. Presentation
- C. Application
- D. Transport
Answer: Application
9. Which OSI layer is responsible for routing packets between networks?
- A. Data Link
- B. Network
- C. Transport
- D. Session
Answer: Network
10. Which OSI layer handles reliable end-to-end delivery?
- A. Network
- B. Transport
- C. Session
- D. Data Link
Answer: Transport
11. Which OSI layer deals with MAC addresses and framing?
- A. Physical
- B. Data Link
- C. Network
- D. Transport
Answer: Data Link
12. Which OSI layer handles encryption and data format translation?
- A. Session
- B. Presentation
- C. Application
- D. Transport
Answer: Presentation
13. How many layers does the TCP/IP model have?
- A. 3
- B. 4
- C. 5
- D. 7
Answer: 4
14. Which protocol provides reliable, connection-oriented delivery?
- A. UDP
- B. TCP
- C. IP
- D. ICMP
Answer: TCP
15. Which protocol is connectionless and does not guarantee delivery?
- A. TCP
- B. UDP
- C. FTP
- D. HTTP
Answer: UDP
16. Which protocol is used to transfer web pages?
- A. FTP
- B. HTTP
- C. SMTP
- D. SNMP
Answer: HTTP
17. Which protocol is used to transfer files between computers?
- A. HTTP
- B. FTP
- C. SMTP
- D. DNS
Answer: FTP
18. Which protocol is used to send email?
- A. POP3
- B. SMTP
- C. IMAP
- D. HTTP
Answer: SMTP
19. Which protocols are used to receive email?
- A. SMTP and FTP
- B. POP3 and IMAP
- C. HTTP and HTTPS
- D. TCP and UDP
Answer: POP3 and IMAP
20. What does DNS do?
- A. Assigns IP addresses automatically
- B. Translates domain names into IP addresses
- C. Encrypts web traffic
- D. Routes packets
Answer: Translates domain names into IP addresses
21. Which protocol automatically assigns IP addresses to devices?
- A. DNS
- B. DHCP
- C. ARP
- D. ICMP
Answer: DHCP
22. Which protocol maps an IP address to a MAC address?
- A. DNS
- B. ARP
- C. DHCP
- D. RARP
Answer: ARP
23. Which protocol does the ping command use?
- A. TCP
- B. ICMP
- C. UDP
- D. HTTP
Answer: ICMP
24. How many bits are in an IPv4 address?
- A. 16
- B. 32
- C. 64
- D. 128
Answer: 32
25. How many bits are in an IPv6 address?
- A. 32
- B. 64
- C. 128
- D. 256
Answer: 128
26. Which IP address class has the default subnet mask 255.255.255.0?
- A. Class A
- B. Class B
- C. Class C
- D. Class D
Answer: Class C
27. Which IP address class has the default subnet mask 255.0.0.0?
- A. Class A
- B. Class B
- C. Class C
- D. Class D
Answer: Class A
28. Which address is reserved as the loopback address in IPv4?
- A. 192.168.0.1
- B. 127.0.0.1
- C. 255.255.255.255
- D. 0.0.0.0
Answer: 127.0.0.1
29. Which of these is a private IP address range?
- A. 8.8.8.0/24
- B. 192.168.0.0/16
- C. 203.0.113.0/24
- D. 1.1.1.0/24
Answer: 192.168.0.0/16
30. What is the default port number for HTTP?
- A. 21
- B. 25
- C. 80
- D. 443
Answer: 80
31. What is the default port number for HTTPS?
- A. 80
- B. 443
- C. 8080
- D. 22
Answer: 443
32. What is the default port number for FTP control?
- A. 20
- B. 21
- C. 22
- D. 23
Answer: 21
33. What is the default port number for SSH?
- A. 21
- B. 22
- C. 23
- D. 25
Answer: 22
34. What is the default port number for SMTP?
- A. 21
- B. 25
- C. 110
- D. 143
Answer: 25
35. What is the default port number for DNS?
- A. 43
- B. 53
- C. 63
- D. 73
Answer: 53
36. Which network topology connects all devices to a single central cable?
- A. Star
- B. Bus
- C. Ring
- D. Mesh
Answer: Bus
37. Which network topology connects all devices to a central hub or switch?
- A. Bus
- B. Star
- C. Ring
- D. Tree
Answer: Star
38. Which topology connects every device to every other device?
- A. Star
- B. Bus
- C. Mesh
- D. Ring
Answer: Mesh
39. In which topology does data travel in one direction around a loop?
- A. Bus
- B. Star
- C. Ring
- D. Mesh
Answer: Ring
40. Which topology is most reliable but uses the most cable?
- A. Bus
- B. Star
- C. Ring
- D. Mesh
Answer: Mesh
41. Which device connects two different networks and routes traffic between them?
- A. Hub
- B. Switch
- C. Router
- D. Repeater
Answer: Router
42. Which device forwards data only to the intended port using MAC addresses?
- A. Hub
- B. Switch
- C. Repeater
- D. Modem
Answer: Switch
43. Which device simply broadcasts incoming data to all its ports?
- A. Switch
- B. Hub
- C. Router
- D. Bridge
Answer: Hub
44. Which device converts digital signals to analog and back for telephone lines?
- A. Router
- B. Modem
- C. Switch
- D. Hub
Answer: Modem
45. Which device amplifies a signal to extend network distance?
- A. Repeater
- B. Router
- C. Gateway
- D. Firewall
Answer: Repeater
46. At which OSI layer does a router operate?
- A. Physical
- B. Data Link
- C. Network
- D. Transport
Answer: Network
47. At which OSI layer does a switch normally operate?
- A. Physical
- B. Data Link
- C. Network
- D. Session
Answer: Data Link
48. How many bits are in a MAC address?
- A. 32
- B. 48
- C. 64
- D. 128
Answer: 48
49. What is bandwidth in networking?
- A. The physical width of a cable
- B. The maximum data transfer rate of a connection
- C. The distance a signal travels
- D. The number of devices connected
Answer: The maximum data transfer rate of a connection
50. What is latency in networking?
- A. Data transfer rate
- B. The delay before data begins transferring
- C. Signal strength
- D. Packet size
Answer: The delay before data begins transferring
51. Which transmission mode allows data to flow in both directions at once?
- A. Simplex
- B. Half duplex
- C. Full duplex
- D. Multiplex
Answer: Full duplex
52. Which transmission mode allows data flow in one direction only?
- A. Simplex
- B. Half duplex
- C. Full duplex
- D. Duplex
Answer: Simplex
53. Which cable type is most resistant to electromagnetic interference?
- A. Coaxial
- B. Twisted pair
- C. Fibre optic
- D. Ribbon
Answer: Fibre optic
54. Which connector is normally used with Ethernet twisted-pair cable?
- A. BNC
- B. RJ-45
- C. RJ-11
- D. USB-C
Answer: RJ-45
55. What is a firewall used for?
- A. Speeding up the network
- B. Filtering traffic to protect a network from unauthorised access
- C. Assigning IP addresses
- D. Storing web pages
Answer: Filtering traffic to protect a network from unauthorised access
56. What does VPN stand for?
- A. Virtual Private Network
- B. Verified Public Node
- C. Variable Packet Number
- D. Virtual Protocol Name
Answer: Virtual Private Network
57. What is a gateway in networking?
- A. A physical door to the server room
- B. A node that connects two networks using different protocols
- C. A cable connector
- D. A type of firewall rule
Answer: A node that connects two networks using different protocols
58. What does the client-server model describe?
- A. Two equal computers sharing files
- B. Clients requesting services from a central server
- C. A wireless standard
- D. A cable layout
Answer: Clients requesting services from a central server
59. In a peer-to-peer network, what is true of the computers?
- A. One controls all others
- B. Each can act as both client and server
- C. They must run the same OS
- D. They cannot share files
Answer: Each can act as both client and server
60. Which wireless standard family is commonly called Wi-Fi?
- A. IEEE 802.3
- B. IEEE 802.11
- C. IEEE 802.15
- D. IEEE 802.16
Answer: IEEE 802.11
61. Which IEEE standard defines wired Ethernet?
- A. 802.3
- B. 802.11
- C. 802.15
- D. 802.5
Answer: 802.3
62. What does NAT do?
- A. Encrypts traffic
- B. Translates private IP addresses to a public one
- C. Assigns domain names
- D. Blocks viruses
Answer: Translates private IP addresses to a public one
63. What is a packet in networking?
- A. A physical box of hardware
- B. A formatted unit of data carried across a network
- C. A network cable
- D. A software licence
Answer: A formatted unit of data carried across a network
Frequently asked questions
How many Computer Networks questions are in this test?
This page has 63 Computer Networks MCQs with answers. Each attempt picks 25 of them at random.
Is the Computer Networks test free?
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Can I get a certificate for this test?
Score 50% or more and you can claim a certificate from Alien Institute of Computer at 40% off. The WhatsApp button appears on your result screen.