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

How many bits does an IPv4 address have?

  1. A32
  2. B16
  3. C64
  4. D128
2.Easy

What is the main job of a firewall?

  1. ATo speed up downloads by caching files
  2. BTo assign IP addresses to hosts
  3. CTo allow or block traffic according to security rules
  4. DTo convert domain names into addresses
3.Easy

What is throughput?

  1. AThe rate at which data is actually delivered successfully
  2. BThe number of routers on a path
  3. CThe theoretical maximum rate a link can carry under ideal conditions
  4. DThe time a packet takes to cross a link
4.Medium

Which subnet mask corresponds to /20?

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

Which of these is a private IPv4 address range?

  1. A100.0.0.0/8
  2. B8.8.8.0/24
  3. C192.168.0.0/16
  4. D200.1.1.0/24
6.Medium

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

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

A remote-terminal application feels sluggish because small keystroke packets are held back. Which TCP mechanism is often responsible?

  1. ANagle's algorithm
  2. BThe three-way handshake
  3. CFast retransmit
  4. DSlow start
8.Hard

TCP congestion control's "slow start" phase:

  1. AHalves the congestion window every round trip until a packet loss is detected
  2. BKeeps the window fixed at one segment
  3. CIs used only by UDP
  4. DIncreases the congestion window exponentially until a threshold or loss

Answer key

  1. 1. A · 32
  2. 2. C · To allow or block traffic according to security rules
  3. 3. A · The rate at which data is actually delivered successfully
  4. 4. B · 255.255.240.0
  5. 5. C · 192.168.0.0/16
  6. 6. D · The destination MAC address is not yet in its address table
  7. 7. A · Nagle's algorithm
  8. 8. D · Increases the congestion window exponentially until a threshold or loss

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