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

  1. ADHCP
  2. BSMTP
  3. CFTP
  4. DDNS
2.Easy

Which protocol gives secure, encrypted remote login to another computer?

  1. AFTP
  2. BTelnet
  3. CSSH
  4. DSNMP
3.Easy

How many layers does the OSI reference model have?

  1. A5
  2. B7
  3. C9
  4. D4
4.Medium

Which subnet mask corresponds to /20?

  1. A255.255.224.0
  2. B255.255.248.0
  3. C255.255.240.0
  4. D255.255.255.240
5.Medium

What is the usual order of messages when a client obtains an address from DHCP?

  1. ADiscover, Offer, Request, Acknowledge
  2. BOffer, Discover, Acknowledge, Request
  3. CDiscover, Request, Offer, Acknowledge
  4. DRequest, Offer, Discover, Acknowledge
6.Medium

How does TLS typically use asymmetric and symmetric cryptography?

  1. AOnly asymmetric cryptography is used throughout
  2. BAsymmetric methods agree keys and authenticate; symmetric ciphers encrypt the data
  3. CSymmetric methods agree keys and authenticate; asymmetric ciphers encrypt all the data
  4. DOnly symmetric cryptography is used, with a fixed shared password
7.Hard

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

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

DNS queries normally use UDP. When does DNS typically use TCP instead?

  1. AOnly when the domain name is longer than ten characters
  2. BOnly for reverse lookups of IP addresses
  3. CFor responses too large for UDP and for zone transfers
  4. DFor every query sent from a web browser

Answer key

  1. 1. A · DHCP
  2. 2. C · SSH
  3. 3. B · 7
  4. 4. C · 255.255.240.0
  5. 5. A · Discover, Offer, Request, Acknowledge
  6. 6. B · Asymmetric methods agree keys and authenticate; symmetric ciphers encrypt the data
  7. 7. A · Victims send traffic for the gateway to the attacker, enabling a man-in-the-middle attack
  8. 8. C · For responses too large for UDP and for zone transfers

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