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 IPv4 address is the standard loopback address of a host?

  1. A0.0.0.0
  2. B127.0.0.1
  3. C255.255.255.255
  4. D192.168.0.1
2.Easy

What is a network interface card (NIC)?

  1. ASoftware that resolves domain names
  2. BA server that stores web pages
  3. CA cable that links two routers
  4. DHardware that connects a computer to a network
3.Easy

How many bits does an IPv4 address have?

  1. A32
  2. B64
  3. C16
  4. D128
4.Medium

Which metric does RIP use to choose routes?

  1. AMeasured delay
  2. BBusiness policy
  3. CHop count
  4. DLink bandwidth
5.Medium

Why does a switch sometimes send a frame out of all ports except the one it came in on?

  1. AThe destination MAC address is not yet in its address table
  2. BThe switch is acting as a router
  3. CThe frame has a wrong IP checksum and must be checked by every host
  4. DThe frame is too large for one port
6.Medium

What is a cyclic redundancy check (CRC) used for in Ethernet frames?

  1. ADetecting transmission errors
  2. BChoosing the best route
  3. CEncrypting the frame
  4. DCorrecting every bit error automatically
7.Hard

Why does TCP choose an unpredictable initial sequence number for each connection?

  1. ATo compress the data more efficiently
  2. BTo avoid confusion with old segments and make spoofed segments harder to inject
  3. CTo select the best route to the destination for the segments of that connection
  4. DTo encrypt the payload of each segment
8.Hard

Why does a browser warn when a site presents a self-signed certificate?

  1. AThe site must be using HTTP instead of HTTPS
  2. BSelf-signed certificates use no encryption at all, so the traffic is sent in clear text
  3. CThe certificate is always expired
  4. DNo trusted certificate authority vouches that the key belongs to that site

Answer key

  1. 1. B · 127.0.0.1
  2. 2. D · Hardware that connects a computer to a network
  3. 3. A · 32
  4. 4. C · Hop count
  5. 5. A · The destination MAC address is not yet in its address table
  6. 6. A · Detecting transmission errors
  7. 7. B · To avoid confusion with old segments and make spoofed segments harder to inject
  8. 8. D · No trusted certificate authority vouches that the key belongs to that site

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