Designing a network from requirements

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Designing a network from requirements

Name:
Date:
Class:
A

Quick Questions

Shade in the A or B circle for each question.

1. A school library needs 30 reliable computers with no dropped connections. Which cabling choice best meets this requirement?
A Wired Ethernet to each computer
B Wi-Fi only, to save on cabling
2. Which step comes FIRST when designing a network from user requirements?
A List what the users need (devices, speed, security, budget)
B Buy the most expensive router available
3. A small office needs 20 wired computers connected in a star topology. Which device should sit at the centre?
A A network switch
B A modem
4. A designer plans the IP address range 192.168.1.0 for an office LAN. Which type of address is this?
A A public IPv4 address range
B A private IPv4 address range
5. Which part of an IP address plan is the best way to give servers and printers a fixed address?
A Let DHCP choose a new address each time
B Assign static IP addresses
B

Match the Pairs

Draw a line connecting each item on the left to its match on the right.

Left columnRight column
1Requirement: 30 users, 100 Mbps each AThe design does not meet the security requirement; it needs WPA3 or WPA2 encryption, a strong password and separation from guests.
2192.168.10.0/24 - Staff, 192.168.20.0/24 - Guests BThe default gateway 192.168.1.256 is invalid because each IPv4 octet must be 0 to 255; use a valid address such as 192.168.1.1.
3Justifying a trade-off: choose a wired star network for the office because it is faster and more reliable, even though cabling costs more CChoice: Ethernet star with switch | Reason: speed and reliability | Cost: higher cabling
4Selecting a device to meet a security requirement: guest traffic must be kept away from the staff file server DAn IP address plan giving each group its own subnet so they can be kept separate
5Design: 5 devices on 192.168.1.0/24. Gateway 192.168.1.256 EA requirements list item that sets a measurable target, used to choose devices, cabling and bandwidth
6Requirement: staff data must be private. Design: free public Wi-Fi, no password FAdd router + firewall rule: DENY Guest subnet -> Staff subnet
C

Definitions

network design
D

Fill in the Blanks

Complete each line of code by filling in the missing parts.

1.
need: one cable fault must not stop others topology: ____
2.
network: 192.168.1.0/24 mask: _____________
3.
need: block outside traffic to the network control: ________
4.
need: link two buildings 400 m apart media: _____ optic cable
5.
need: 100 laptops join and leave daily addressing: ____
E

Spot the Error

Shade in the letter of the line that contains an error.

Question 1
A Requirement: 20 users
B Device: switch with 8 ports
C Medium: Ethernet cable
D Topology: star
Question 2
A Need: guests use Wi-Fi
B Device: wireless access point
C Guest network: separate VLAN
D Guest access: full LAN access
Question 3
A Subnet mask: 255.255.256.0
B Network: 192.168.1.0
C Router: 192.168.1.1
D Printer: 192.168.1.50
Question 4
A Subnet: /24 gives 24 hosts
B Devices needed: 120
C Result: subnet is big enough
Question 5
A Requirement: very fast links
B Medium: fibre optic cable
C Reason: high bandwidth
D Trade-off: lower cost

Answer Key

Designing a network from requirements
Section A: Quick Questions
Q1
A — Wired Ethernet to each computer
Q2
A — List what the users need (devices, speed, security, budget)
Q3
A — A network switch
Q4
B — A private IPv4 address range
Q5
B — Assign static IP addresses
Section B: Match the Pairs
Q1
Requirement: 30 users, 100 Mbps each → A requirements list item that sets a measurable target, used to choose devices, cabling and bandwidth
Q2
192.168.10.0/24 - Staff, 192.168.20.0/24 - Guests → An IP address plan giving each group its own subnet so they can be kept separate
Q3
Justifying a trade-off: choose a wired star network for the office because it is faster and more reliable, even though cabling costs more → Choice: Ethernet star with switch | Reason: speed and reliability | Cost: higher cabling
Q4
Selecting a device to meet a security requirement: guest traffic must be kept away from the staff file server → Add router + firewall rule: DENY Guest subnet -> Staff subnet
Q5
Design: 5 devices on 192.168.1.0/24. Gateway 192.168.1.256 → The default gateway 192.168.1.256 is invalid because each IPv4 octet must be 0 to 255; use a valid address such as 192.168.1.1.
Q6
Requirement: staff data must be private. Design: free public Wi-Fi, no password → The design does not meet the security requirement; it needs WPA3 or WPA2 encryption, a strong password and separation from guests.
Section C: Definitions
Q1
network design — Turning user requirements into a plan by choosing devices, media, topology, IP addressing and security controls, then justifying each choice.
Section D: Fill in the Blanks
Q1
need: one cable fault must not stop others topology: star
Q2
network: 192.168.1.0/24 mask: 255.255.255.0
Q3
need: block outside traffic to the network control: firewall
Q4
need: link two buildings 400 m apart media: fibre optic cable
Q5
need: 100 laptops join and leave daily addressing: DHCP
Section E: Spot the Error
Q1
B — A switch with only 8 ports cannot connect 20 users. The device must meet the requirement, so it should be a switch with 24 ports.
Q2
D — Guests on a separate network should be segregated from internal resources. Their access should be internet only, not full LAN access.
Q3
A — Each octet of a subnet mask must be between 0 and 255, so 256 is invalid. The mask should be 255.255.255.0.
Q4
A — A /24 subnet gives 254 usable host addresses, not 24. Only 254 hosts makes the result (big enough for 120 devices) correct.
Q5
D — Fibre optic cable and its equipment cost more than copper Ethernet. The trade-off for the high bandwidth is higher cost.