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

In networking, a protocol is:

  1. AA physical cable between two devices
  2. BA list of all devices on a network
  3. CA set of rules for the format and order of messages
  4. DA program that blocks viruses
2.Easy

What is the default port number for HTTPS?

  1. A25
  2. B21
  3. C80
  4. D443
3.Easy

Which protocol lets an email client read mail while keeping messages and folders on the server?

  1. ADHCP
  2. BSNMP
  3. CSMTP
  4. DIMAP
4.Medium

Which IPv4 header field stops packets from circulating forever in a routing loop?

  1. AIdentification
  2. BTime to live (TTL)
  3. CHeader checksum
  4. DType of service
5.Medium

What does a subnet mask of 255.255.255.0 correspond to in CIDR notation?

  1. A/24
  2. B/16
  3. C/8
  4. D/32
6.Medium

Which protocol does the "ping" command use?

  1. AUDP
  2. BTCP
  3. CHTTP
  4. DICMP
7.Hard

Which mechanism prevents broadcast loops in a network with redundant switch links?

  1. ADHCP snooping
  2. BSpanning Tree Protocol
  3. CARP caching
  4. DNAT
8.Hard

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

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

Answer key

  1. 1. C · A set of rules for the format and order of messages
  2. 2. D · 443
  3. 3. D · IMAP
  4. 4. B · Time to live (TTL)
  5. 5. A · /24
  6. 6. D · ICMP
  7. 7. B · Spanning Tree Protocol
  8. 8. B · Victims send traffic for the gateway to the attacker, enabling a man-in-the-middle attack

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