Computer Knowledge

Computer Networks

2,614 Questions

Computer networks involve the architecture, protocols, and security measures used for digital communication. This collection covers OSI model layers, IP addressing, data transmission, and cryptographic standards. These concepts are vital for the computer knowledge sections of banking and government exams.

OSI model layersNetwork protocolsIP subnet maskingData encryption standardsServer configurationsNetwork commands

Computer Networks Questions

Multiple choice

DNS uses port number:

  1. 53

  2. 69

  3. 20 and 21

  4. 47
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

DNS (Domain Name System) uses port 53 for both UDP and TCP queries.

Multiple choice

__________ are used on Firewalls to block ports

  1. ACLs

  2. Group Policy

  3. ICMP Controls

  4. FTP Blocking Sites
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Access Control Lists (ACLs) are sets of rules applied to firewall interfaces to permit or deny traffic based on IP addresses, protocols, or ports.

Multiple choice

VoIP data uses:

  1. TCP Ports 5050 and 5051

  2. UDP Ports 5050 and 5051

  3. TCP Port 67 and 68

  4. UDP Port 3389
Reveal answer Fill a bubble to check yourself
A Correct answer
Multiple choice

Secure Mail uses these three ports:

  1. 587, 993, 995

  2. 25, 143, 110

  3. 20, 65, 53

  4. 3389, 5050, 5051
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Secure email transmission typically uses SMTPS (587), IMAPS (993), and POP3S (995). These ports provide encrypted communication channels for mail services.

Multiple choice

TFTP is secure and uses Port 69

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Trivial File Transfer Protocol (TFTP) is inherently insecure because it does not provide authentication or encryption. It uses port 69.

Multiple choice

What happens when an untagged frame is received by a trunk port?

  1. the port shuts down because of a security violation

  2. they are forwarded to the native VLAN

  3. they are flooded to all ports, regardless of VLAN

  4. they are immediately dropped
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

When a trunk port receives an untagged frame, it assumes the frame belongs to the configured native VLAN for that trunk.

Multiple choice

User needs work access at home. Set router port forwarding didn't fix. What is NEXT step

  1. Configure Wake-on-LAN for the NIC on the Work PC.

  2. Switch the Work PC network from “Work” to “Home”.

  3. Configure a firewall exception on the Home PC.

  4. Disable the Windows firewall on the Home PC.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

If port forwarding is configured correctly on the router but access fails, the local firewall on the target PC is likely blocking the incoming connection.