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 is the name of the data unit at the data link layer?

  1. APacket
  2. BFrame
  3. CMessage
  4. DSegment
2.Easy

What is the default port number for HTTPS?

  1. A21
  2. B25
  3. C80
  4. D443
3.Easy

Which device simply repeats every incoming signal out of all its other ports?

  1. AA hub
  2. BA switch
  3. CA router
  4. DA firewall
4.Medium

NAT (network address translation) is mainly used to:

  1. ALet many devices with private addresses share one public IP address
  2. BIncrease the speed of a network cable
  3. CTranslate domain names into IP addresses for devices on a local network
  4. DEncrypt traffic between two sites
5.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
6.Medium

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

  1. ADiscover, Request, Offer, Acknowledge
  2. BRequest, Offer, Discover, Acknowledge
  3. COffer, Discover, Acknowledge, Request
  4. DDiscover, Offer, Request, Acknowledge
7.Hard

Stations A and C both reach access point B but cannot hear each other, so their frames collide at B. How does 802.11 help?

  1. ABy making A and C use collision detection so they stop sending when frames overlap
  2. BOptional RTS/CTS exchanges: the AP's CTS tells all nearby stations to wait
  3. CBy routing A's frames through C
  4. DBy increasing the TTL of the frames
8.Hard

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

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

Answer key

  1. 1. B · Frame
  2. 2. D · 443
  3. 3. A · A hub
  4. 4. A · Let many devices with private addresses share one public IP address
  5. 5. B · Time to live (TTL)
  6. 6. D · Discover, Offer, Request, Acknowledge
  7. 7. B · Optional RTS/CTS exchanges: the AP's CTS tells all nearby stations to wait
  8. 8. D · For responses too large for UDP and for zone transfers

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