1.4 · Setting up Ethernet & Wi-Fi

Goal: outline the practical steps for a small wired and wireless network.

Wired (Ethernet) setup

1. Pull cables (Cat5e or Cat6) from each device to a central switch.
2. Patch panel + switch in the cabinet aggregate all cables.
3. Switch uplink goes to the router.
4. Router assigns IPs via DHCP and connects to the ISP modem.
5. Configure each device to Obtain IP automatically (DHCP).
6. Test connectivity with ping and a browser.

Wireless (Wi-Fi) setup

1. Choose Wi-Fi standard — Wi-Fi 5 (802.11ac) or Wi-Fi 6 (802.11ax) for modern speed.
2. Place AP centrally; multiple APs for large coverage (with same SSID for roaming).
3. Configure SSID — the network name.
4. Security — WPA2-Personal at minimum; WPA3 if all devices support it.
5. Set a strong passphrase (≥ 12 chars, mixed).
6. Optionally create a guest network with isolation from the main LAN.
7. Channel — auto or manually select (1, 6, 11 for 2.4 GHz).

Configuration interface

Most routers and APs expose a web admin UI:

1. Connect to 192.168.1.1 (or as printed on the device).
2. Log in with admin credentials.
3. Update firmware.
4. Change default admin password!
5. Configure DHCP range, Wi-Fi SSID, security.

Test the connection

Command	Purpose
ipconfig (Windows) / ifconfig / ip a (Linux/macOS)	Check IP, gateway
ping 8.8.8.8	Test Internet reachability
nslookup example.com	Test DNS
tracert / traceroute	Trace the route

Common student mistakes

• Leaving default admin password (router becomes hackable).
• Using WEP (broken) or open Wi-Fi.
• Putting all APs on the same channel → interference.
• Not separating guest Wi-Fi from internal LAN.

Exam-style question

Q (5 marks): Outline the steps to set up a small office wireless network for 10 staff PCs, an IP printer, and visitor laptops. Mention two security considerations.

Sample answer:

1. Plan: choose a Wi-Fi 6 router with at least 4 LAN ports (or add a switch). Position the AP centrally to cover all rooms.
2. Wire essentials: connect the printer and a couple of fixed PCs via Ethernet for stability; connect the router to the ISP modem.
3. Configure router: log in, change default admin password, update firmware, set WAN to DHCP from ISP.
4. Set Wi-Fi: choose SSID "Office", enable WPA3 (or WPA2-Personal) with a strong passphrase, place on 5 GHz channel.
5. Create guest network: separate SSID "Office-Guest" isolated from main LAN, perhaps with a captive portal.
6. Test: connect each PC, ping the printer, browse the Internet.

Two security considerations:

• WPA3 / WPA2-Personal with a strong passphrase — prevents eavesdropping on the wireless link.
• Guest network isolation — keeps visitor devices from reaching internal printers and shared drives.

Key takeaways

• Choose appropriate Wi-Fi standard.
• Always use WPA2/3 and a strong passphrase.
• Separate guest and internal networks.

➡️ Next: 1.5 File Sharing & Permissions