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.

New worksheetPractise online with hints

For teachers: free to print, copy and use in class. Every new worksheet has new values and its own answer key. A link to ExamProblems on your course page is appreciated.

Name: ____________________   Date: ____________

1.Easy

What is the default port number for DNS?

  1. A53
  2. B80
  3. C67
  4. D161
2.Easy

Which IEEE standard family defines Wi-Fi wireless LANs?

  1. AIEEE 802.11
  2. BIEEE 802.15
  3. CIEEE 802.1Q
  4. DIEEE 802.3
3.Easy

What does a VPN mainly provide?

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

Which of these is a private IPv4 address range?

  1. A100.0.0.0/8
  2. B192.168.0.0/16
  3. C200.1.1.0/24
  4. D8.8.8.0/24
5.Medium

What is the main purpose of a VLAN?

  1. ATo increase the speed of every switch port
  2. BTo split one physical switched network into separate broadcast domains
  3. CTo give each device a public IP address
  4. DTo encrypt all traffic between switches so other departments cannot read it
6.Medium

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

  1. ADiscover, Request, Offer, Acknowledge
  2. BOffer, Discover, Acknowledge, Request
  3. CRequest, Offer, Discover, Acknowledge
  4. DDiscover, Offer, Request, Acknowledge
7.Hard

Why was the TCP window scale option introduced?

  1. AUDP needed a way to control its sending rate on congested paths
  2. BWithout it, TCP could not detect lost segments on long-distance links
  3. CThe 32-bit window field was too large and wasted header space in every TCP segment sent
  4. DThe 16-bit window field limits the window to 65,535 bytes, too small for fast long-distance paths
8.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. ATurn off the PC's DNS client
  2. BGive the PC a different MAC address so the router can find it from outside
  3. CChange the PC's subnet mask to /32
  4. DConfigure port forwarding on the router to the PC's private address

Answer key

  1. 1. A · 53
  2. 2. A · IEEE 802.11
  3. 3. B · An encrypted tunnel across an untrusted network such as the internet
  4. 4. B · 192.168.0.0/16
  5. 5. B · To split one physical switched network into separate broadcast domains
  6. 6. D · Discover, Offer, Request, Acknowledge
  7. 7. D · The 16-bit window field limits the window to 65,535 bytes, too small for fast long-distance paths
  8. 8. D · Configure port forwarding on the router to the PC's private address

Full step-by-step solutions: practise this topic on examproblems.com.