Computer networks worksheet with answers

Free printable Computer networks worksheet: 8 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

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Name: ____________________   Date: ____________

1.Easy

What does DNS do?

  1. ATranslates domain names into IP addresses
  2. BAssigns IP addresses to devices automatically
  3. CRoutes packets between networks
  4. DEncrypts web traffic
2.Easy

In a peer-to-peer network:

  1. AOnly routers may share files
  2. BOne central server handles every request
  3. CEach node can act as both a client and a server
  4. DDevices cannot communicate directly
3.Easy

What does a VPN mainly provide?

  1. AA faster physical connection to the internet through a dedicated line
  2. BAn encrypted tunnel across an untrusted network such as the internet
  3. CA free public IP address for every device
  4. DAutomatic backup of files to a server
4.Medium

How long does it take to put a 1500-byte packet onto a 12 Mbit/s link (transmission delay)?

  1. A12 ms
  2. B8 ms
  3. C0.125 ms
  4. D1 ms
5.Medium

A browser receives HTTP status code 404. What does it mean?

  1. AThe request succeeded
  2. BThe requested resource was not found
  3. CThe client must log in first
  4. DThe server had an internal error
6.Medium

What is the purpose of the TCP three-way handshake?

  1. ATo find the IP address of a host before data can be sent to it
  2. BTo close a connection quickly
  3. CTo encrypt the data
  4. DTo establish a connection and synchronise sequence numbers
7.Hard

How does fragmentation differ in IPv6 compared with IPv4?

  1. AIPv6 routers fragment every packet larger than 64 bytes before forwarding it on the path
  2. BIPv6 fragments at the transport layer inside TCP
  3. CIPv6 does not allow packets larger than 576 bytes
  4. DRouters never fragment IPv6 packets; only the source can, using path MTU discovery
8.Hard

An attacker on a LAN sends forged ARP replies claiming the gateway's IP address. What is the likely result?

  1. AThe gateway's IP address is permanently changed to the attacker's address on every router
  2. BAll DNS queries fail across the internet
  3. CVictims send traffic for the gateway to the attacker, enabling a man-in-the-middle attack
  4. DThe switch shuts down all of its ports

Answer key

  1. 1. A · Translates domain names into IP addresses
  2. 2. C · Each node can act as both a client and a server
  3. 3. B · An encrypted tunnel across an untrusted network such as the internet
  4. 4. D · 1 ms
  5. 5. B · The requested resource was not found
  6. 6. D · To establish a connection and synchronise sequence numbers
  7. 7. D · Routers never fragment IPv6 packets; only the source can, using path MTU discovery
  8. 8. C · Victims send traffic for the gateway to the attacker, enabling a man-in-the-middle attack

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