Wi-Fi for a Two-Storey Office
A small accounting firm moves into a two-storey building with thick concrete walls and metal filing cabinets. There are 25 staff, each with a laptop, plus 4 shared printers and a server holding client records. The firm installs one wireless router on the ground floor. Staff upstairs report weak signals, dropped connections and slow access to the server, while staff near the router get good speeds. The firm also wants visitors to use the internet without reaching client records. The budget allows either extra access points or cabling, but not both in every room.
1. Diagnose the cause of the poor connections and recommend a network design, justifying your choices.
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The symptoms are classic wireless coverage and interference problems. One router cannot cover two floors through thick concrete, and metal cabinets absorb and reflect signals. Upstairs staff are far from the router, so signal strength drops and connections fail. The server is also shared over Wi-Fi, so 25 laptops compete for one wireless channel, which explains slow access.
The recommended design:
- Cable the fixed devices: connect the server and the 4 printers by Ethernet. They do not move, and cabling gives fast, stable, secure links.
- Add access points on each floor, connected by cable back to the router or a switch, so wireless coverage reaches everywhere.
- Separate visitor access using a guest network that can reach the internet but not the server or client records.
This splits the budget sensibly: cabling where devices are fixed and wireless where staff move. It also improves security, because client records stay on a wired, controlled part of the network.
2. Explain the security risk of letting visitors use the same wireless network as staff, and how a guest network reduces it.
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On a single shared network, visitors and staff devices are on the same segment. A visitor's infected laptop could spread malware to staff machines, and a curious visitor might try to reach the server holding client records. Shared passwords also mean the firm cannot tell who did what.
A guest network puts visitor traffic on a separate segment with its own password. It allows internet access but blocks access to the server and staff devices, usually through firewall rules. The password can be changed often, and visitor activity can be logged separately.
This does not remove all risk, because a guest could still attack other guests, but it protects the firm's most valuable asset, the client records, which is the priority for an accounting firm.