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 SSH?

  1. A22
  2. B23
  3. C53
  4. D110
2.Easy

What is throughput?

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

In networking, a protocol is:

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

What is the main purpose of a VLAN?

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

Why is UDP often preferred for live video calls?

  1. ALow delay matters more than retransmitting every lost packet
  2. BUDP is required for all video
  3. CUDP guarantees every packet arrives, so the picture never freezes
  4. DUDP encrypts data automatically
6.Medium

NAT (network address translation) is mainly used to:

  1. ATranslate domain names into IP addresses for devices on a local network
  2. BEncrypt traffic between two sites
  3. CLet many devices with private addresses share one public IP address
  4. DIncrease the speed of a network cable
7.Hard

Which of these addresses is a public (not RFC 1918 private) IPv4 address?

  1. A172.32.0.1
  2. B172.31.0.1
  3. C10.255.0.1
  4. D192.168.255.1
8.Hard

In a TCP connection, what does the receive window (rwnd) control?

  1. AThe number of open ports
  2. BThe size of each IP packet header
  3. CHow much unacknowledged data the sender may send, based on the receiver's buffer
  4. DThe retransmission time-out, calculated from the measured round-trip time of each segment

Answer key

  1. 1. A · 22
  2. 2. A · The rate at which data is actually delivered successfully
  3. 3. A · A set of rules for the format and order of messages
  4. 4. D · To split one physical switched network into separate broadcast domains
  5. 5. A · Low delay matters more than retransmitting every lost packet
  6. 6. C · Let many devices with private addresses share one public IP address
  7. 7. A · 172.32.0.1
  8. 8. C · How much unacknowledged data the sender may send, based on the receiver's buffer

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