Predict: Network Scenarios
Test your intuition about networks before learning the details
How This Works
For each scenario, predict the answer before revealing the solution. This helps you engage with the concepts and identify what you already know.
School Network Classification
A school has 200 computers spread across 3 buildings on the same campus. All computers are connected and share resources like printers and the internet.
Is this a LAN or a WAN?
Answer: LAN (Local Area Network)
Why?
- All buildings are on the same campus (small geographical area)
- The network is owned and managed by the school
- Uses private infrastructure (the school's own cables/WiFi)
- Even though it spans multiple buildings, it's still considered local
Key insight: LAN doesn't mean "one building" - it means "one site or campus owned by one organisation."
Bank Branch Network
A bank has branches in 50 different cities across the UK. Each branch needs to access the central customer database and share information with other branches.
Is this a LAN or a WAN?
Answer: WAN (Wide Area Network)
Why?
- Covers a large geographical area (multiple cities)
- Connects multiple LANs (each branch has its own LAN)
- Uses third-party infrastructure (leased lines, internet)
- The bank doesn't own all the cables between cities
Key insight: A WAN connects LANs together over large distances. Each bank branch has a LAN, and the WAN connects all branches.
Slow Internet at Lunchtime
A school notices that their WiFi is fast in the morning but becomes very slow during lunch break when hundreds of students connect their phones.
What is the main factor causing this slowdown?
Answer: Number of Devices Connected
Why?
- The bandwidth is shared between all connected devices
- If 100 Mbps is shared by 200 phones = ~0.5 Mbps each
- More devices = less bandwidth per user
- Also increases network traffic/congestion
Solutions could include: More access points, limiting connections, prioritising traffic, increasing bandwidth.
Small Office Setup
A small office has 4 computers. The staff want to share files with each other, but they have a limited budget and no IT specialist.
Should they use Client-Server or Peer-to-Peer networking?
Answer: Peer-to-Peer (P2P)
Why P2P is better here:
- No expensive server needed
- Easy to set up without IT expertise
- Low cost - just connect the computers
- Only 4 computers - small enough to manage
- Each user can share their own files directly
When would Client-Server be better? If they grew to 50+ computers, needed central backups, or required tight security controls.
Large Hospital Network
A hospital has 500 computers across multiple departments. Patient records must be secure, regularly backed up, and accessible from any computer. They have an IT team.
Should they use Client-Server or Peer-to-Peer networking?
Answer: Client-Server
Why Client-Server is essential here:
- Centralised security - patient data is protected
- Automatic backups from central servers
- Access control - who can see what records
- Scalable - can handle 500+ computers
- IT team can manage everything from one place
- Audit trails - track who accessed what
P2P would be dangerous here - no central control over sensitive medical data!
Connecting to WiFi
A laptop can connect to a wired Ethernet network, but when you unplug it and try to use WiFi, it says "No wireless adapters found."
Which hardware component is missing or broken?
Answer: Wireless NIC (Network Interface Card)
Why?
- The laptop has a wired NIC (Ethernet works)
- But is missing or has a faulty wireless NIC
- Each type of connection needs its own NIC
- The NIC converts data into signals for transmission
Solutions: USB WiFi adapter, repair internal wireless card, or enable it in BIOS/settings if disabled.
Connecting to the Internet
Five computers in an office are connected to a switch and can share files with each other. However, none of them can access the internet.
What hardware is needed to give them internet access?
Answer: Router
Why?
- A switch only connects devices within the same LAN
- A router connects different networks together
- The router directs traffic between the LAN and the internet
- It uses IP addresses to route data to the correct destination
Key difference: Switch = within a network. Router = between networks.
Website Not Loading
You type "www.example.com" in your browser, but get an error "DNS server not responding". However, when you type the IP address 93.184.216.34 directly, the website loads.
What does this tell you about DNS?
Answer: DNS converts domain names to IP addresses
What's happening:
- Your computer can reach the web server (IP works)
- But it can't convert the domain name to an IP
- DNS servers are down or unreachable
- Without DNS, you'd need to memorise IP addresses!
DNS is like a phone book: You look up a name (www.example.com) and get the number (IP address) to call.
Working Offline
A student uses Google Docs to write essays. During a power cut at home, they lose internet but their laptop still works on battery. They cannot access their essay.
What is the main disadvantage of cloud computing shown here?
Answer: Requires Internet Connection
Why this is a problem:
- Cloud services need constant internet access
- No internet = no access to your files
- You're dependent on your connection
- Also dependent on the cloud provider being online
Workarounds: Many cloud apps now offer "offline mode" that syncs when reconnected. Always have local backups of important files!
Company Data Security
A company is considering moving all their confidential business plans to cloud storage. The IT manager is concerned because the company won't physically control where their data is stored.
What cloud computing disadvantage is the IT manager worried about?
Answer: Data Security/Privacy Concerns & Less Control
Valid concerns include:
- Data stored on someone else's servers
- Less control over who can access it
- Data might be stored in different countries with different laws
- Trusting the cloud provider's security measures
- Risk of data breaches at the provider
Mitigations: Encryption, choosing trusted providers, keeping highly sensitive data on-premises.
Adding New Computers
A school IT department needs to add 20 new computers to their network quickly and easily, without disrupting the existing network. They want minimal downtime for other users.
Star or Mesh topology - which is better for this?
Answer: Star Topology
Why Star is better here:
- Easy to add devices - just plug into the switch
- No disruption to existing connections
- Each new computer gets its own cable to the central switch
- Existing devices keep working during setup
Mesh would require: Running cables to multiple existing devices, complex configuration, more disruption.
Critical Systems
An air traffic control centre needs a network where communication MUST continue even if multiple cables or devices fail. Reliability is more important than cost.
Star or Mesh topology - which is better for this?
Answer: Mesh Topology
Why Mesh is essential here:
- Multiple redundant paths between devices
- No single point of failure
- If one connection fails, data takes another route
- Critical systems need maximum reliability
- Cost is secondary to safety (lives at stake)
Star would be risky: If the central switch fails, the entire network goes down - unacceptable for air traffic control!
Your Progress
You've worked through 0 of 12 scenarios.