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

Which transport protocol provides reliable, ordered delivery with acknowledgements?

  1. AUDP
  2. BIP
  3. CTCP
  4. DICMP
2.Easy

What is the default port number for SSH?

  1. A53
  2. B23
  3. C22
  4. D110
3.Easy

Which protocol automatically gives devices an IP address on a local network?

  1. ADHCP
  2. BDNS
  3. CFTP
  4. DSMTP
4.Medium

Which DNS record type maps a host name to an IPv6 address?

  1. AMX
  2. BAAAA
  3. CCNAME
  4. DA
5.Medium

Which metric does RIP use to choose routes?

  1. AMeasured delay
  2. BLink bandwidth
  3. CHop count
  4. DBusiness policy
6.Medium

At which OSI layer does a switch normally operate?

  1. AData link (layer 2)
  2. BTransport (layer 4)
  3. CNetwork (layer 3)
  4. DPhysical (layer 1)
7.Hard

A student runs a game server on a PC behind a home NAT router. Friends on the internet cannot connect. What is the usual fix?

  1. AGive the PC a different MAC address so the router can find it from outside
  2. BConfigure port forwarding on the router to the PC's private address
  3. CChange the PC's subnet mask to /32
  4. DTurn off the PC's DNS client
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. BThe switch shuts down all of its ports
  3. CVictims send traffic for the gateway to the attacker, enabling a man-in-the-middle attack
  4. DAll DNS queries fail across the internet

Answer key

  1. 1. C · TCP
  2. 2. C · 22
  3. 3. A · DHCP
  4. 4. B · AAAA
  5. 5. C · Hop count
  6. 6. A · Data link (layer 2)
  7. 7. B · Configure port forwarding on the router to the PC's private address
  8. 8. C · Victims send traffic for the gateway to the attacker, enabling a man-in-the-middle attack

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