ICTSAS217 Connect a home based local wireless network

A computer network is a set of devices that exchange data and share resources, following agreed rules called protocols, over cables or radio.

Networks are organised in one of two ways:

• Client-server. Some devices (servers) provide resources such as files, printing or sign-in; others (clients) request them. Business networks and the internet work this way.
• Peer-to-peer. Every device has equal standing and can share its own resources directly. A small home network where one laptop shares a folder with another is peer-to-peer.

The physical or logical arrangement of devices and links is the topology:

• Bus: every device on one shared cable. Historic.
• Ring: each device connected to two neighbours in a loop. Historic in LANs.
• Star: every device connected to a central switch or access point. This is how almost every home and office network is built today; a failed device does not affect the others, though the centre is a single point of failure.
• Mesh: devices connected to many others, so traffic has alternative paths. The internet's core is a mesh, and "mesh Wi-Fi" systems borrow the idea for home coverage.

Networks are also described by their reach:

• PAN (personal area network): devices around one person, usually over Bluetooth, such as headphones, a watch, a keyboard.
• LAN (local area network): one home, office or building.
• WLAN (wireless LAN): a LAN that uses radio (Wi-Fi) instead of, or as well as, cables. This unit is about building one.
• WAN (wide area network): networks linking sites across cities or countries. The internet is the largest WAN.

flowchart LR
  ISP[Internet service provider] --- NBN[nbn line or<br/>satellite or 4G/5G]
  NBN --- NTD[nbn connection box<br/>or modem]
  NTD --- GW[Router / gateway<br/>routing, NAT, DHCP,<br/>firewall, Wi-Fi]
  GW -- Ethernet --- PC[Desktop PC]
  GW -- Ethernet --- SW[Switch]
  SW -- PoE --- AP[Extra access point]
  GW -. Wi-Fi .- L[Laptop with WNIC]
  GW -. Wi-Fi .- PR[Wireless printer]
  AP -. Wi-Fi .- PH[Phone and tablet]

• An internet connection from an ISP (in Australia, usually delivered over the nbn, a mobile network, or satellite).
• A modem or network termination device, which converts the signal on the line into Ethernet. For nbn fibre to the premises and fixed wireless, the nbn connection box on the wall does this. For fibre to the node or building, a VDSL2 modem is needed. For HFC (cable), nbn supplies an HFC connection device.
• A router, which joins the home network to the internet, gives devices their local addresses (DHCP), translates between private and public addresses (NAT), and filters traffic with a basic firewall.
• A wireless access point (AP), which provides the Wi-Fi. In most homes the router, switch and access point are one box, often called a gateway or modem-router.
• Network interface cards (NICs) in each device. A wired NIC has an RJ45 Ethernet port; a wireless NIC (WNIC) may be built in or added as a USB adapter or a PCIe card.
• Optionally, a switch (more wired ports), extra access points or mesh nodes (more coverage), and powerline adapters.

A modem and a router are different technologies even when they share a box: the modem connects you to your ISP; the router shares that connection among your devices and lets them talk to each other.

Before configuring a router you need to know how the ISP expects it to connect. The main nbn technologies are:

The Northern Territory's geography makes the last two, and mobile broadband, more common than in the cities. Many remote NT premises rely on satellite. nbn announced in August 2025 that it will replace its Sky Muster geostationary satellite service with low Earth orbit satellite broadband using Amazon's constellation (then called Project Kuiper, since rebranded Amazon Leo), with services expected from 2026; the transition is still under way and timelines have been moving. Many remote households and businesses already use Starlink directly, and 4G and 5G home internet is common where mobile coverage allows. (Telstra, Optus and TPG closed their 3G networks in 2024, so any older 3G backup modem no longer works.)

The connection properties you may need from the ISP:

• Connection protocol. Most nbn ISPs now use IPoE with DHCP, so the router gets its settings automatically once plugged in. Some still use PPPoE, which requires a username and password from the ISP. Some require a VLAN ID.
• Whether the ISP supplies a public IPv4 address, or uses carrier-grade NAT (CGNAT), where many customers share one public address. CGNAT is common on mobile and satellite services, including Starlink, and it stops you reaching devices at home from outside.
• IPv6 support, and DNS server settings if not automatic.
• Whether a static IP address is included or available.

To find out who your ISP is, check the bill or account, read the WAN or internet status page in the router, or look up your public IP address: visit a "what is my IP" site, or run nslookup myip.opendns.com resolver1.opendns.com in Command Prompt, then look the address up with a WHOIS service, which shows the organisation it belongs to.

Wi-Fi is the Wi-Fi Alliance's brand for wireless LANs built to the IEEE 802.11 family of standards. In 2018 the Alliance introduced generation numbers to make them easier to follow.

A few things to note. 802.11g works only at 2.4 GHz (it is 802.11a that uses 5 GHz), and g is backwards compatible with b. The headline figures are theoretical maximums shared between all devices on the access point; real-world throughput is much lower. What changed with Wi-Fi 6 and 7 is less about peak speed and more about efficiency with many devices: OFDMA splits each channel among several devices at once, MU-MIMO sends to several devices simultaneously, and Wi-Fi 7's multi-link operation lets a device use two bands at the same time. The whole network runs at the pace of its weakest link, so a Wi-Fi 7 router gives little benefit to a Wi-Fi 5 laptop.

Bands and channels

• 2.4 GHz travels further and passes through walls better, but it is slower and crowded: microwave ovens, Bluetooth, baby monitors and neighbours' networks all use it. In Australia channels 1 to 13 are available, but channels overlap, so only 1, 6 and 11 can be used side by side without interfering.
• 5 GHz is faster with many more non-overlapping channels, but shorter range and weaker through walls. Some 5 GHz channels require dynamic frequency selection (DFS): the router must listen for weather and defence radar and move off the channel if it detects one.
• 6 GHz (Wi-Fi 6E and 7) is the least congested and supports very wide channels, but has the shortest range. In Australia the lower 6 GHz band (5925 to 6425 MHz) is available for Wi-Fi, and in 2025 the ACMA extended Wi-Fi access up to 6585 MHz, allowing two 320 MHz channels; the rest of the upper 6 GHz band has not been opened in Australia as it has in the United States.

Many routers can use the same network name on all bands and "band steer" each device to the best one. Others keep separate names (such as Home and Home_5G), which makes it easier to test each band deliberately.

Wi-Fi analyser apps on a phone or laptop show nearby networks, their channels and signal strength, and help you pick a less crowded channel. On Windows, netsh wlan show networks mode=bssid lists nearby networks with their channel and signal, and netsh wlan show interfaces shows your current connection's band, channel, radio type and signal quality.

Wi-Fi is radio, and radio waves interact with everything between the access point and the device:

• Reflection: waves bounce off metal and other reflective surfaces, which can cause interference at the receiver. Metal-framed buildings, fridges and mirrors are common culprits.
• Refraction: waves bend when passing into a material where they travel at a different speed, such as glass or water, changing direction and reducing efficiency.
• Diffraction: waves bend around obstacles, leaving weaker "shadow" zones behind them.
• Scattering: rough or uneven surfaces, dust and humidity scatter the signal unpredictably.
• Absorption: materials turn the signal's energy into heat. Water (including people and fish tanks), concrete and brick absorb the most.

Typical losses from common building materials:

Every 3 dB lost halves the signal power, so one concrete wall can cut it to a small fraction. Northern Territory homes add their own problems: besser block and concrete construction, steel-framed buildings, cyclone shutters, and houses with a separate granny flat or shed that needs coverage.

The first fix is placement. Put the router centrally, up high, in the open, away from metal, water and other electronics. Not in a cupboard, and not at one end of the house next to where the nbn line happens to come in.

Extending coverage

• Repeaters (range extenders) receive the Wi-Fi signal and rebroadcast it. They are cheap but have real limits. A single-radio repeater spends half its time talking to clients and half to the router, halving capacity, and many relay on the same band they receive. Many create a second network name. They are a last resort.
• Wired access points give the best result: run an Ethernet cable from the router (or a switch) to a second access point where coverage is needed. Power over Ethernet (PoE) sends power down the same cable, so the access point needs no power point nearby; the switch must have PoE ports, or a PoE injector is used. Business-grade systems from one manufacturer are designed to work together and are managed centrally.
• Mesh Wi-Fi systems use several matched units that coordinate automatically under one network name, handing devices from unit to unit as people move. Wi-Fi 6 and 7 tri-band mesh units reserve a radio for the link between units, and connecting the units by Ethernet (wired backhaul) gives the best performance. For most homes today, mesh is the practical answer.
• Powerline adapters carry network data over the home's electrical wiring to a distant room, and some include an access point.

Running new cables through walls or ceilings is regulated cabling work (see below).

Every device on the network needs an IP address. The router gives them out automatically with DHCP (Dynamic Host Configuration Protocol): a device joins and asks for an address, and the router leases it one from a pool, along with the subnet mask, the default gateway (the router's own address) and DNS servers. The lease expires and is renewed, so a device's address can change over time.

A static IP address is set manually and stays the same. It suits devices that other devices need to find reliably, such as printers, network storage and cameras. The better practice at home is a DHCP reservation: tell the router to always give a particular device (identified by its MAC address) the same address. It stays constant without the risk of two devices being configured with the same address.

Home networks use private address ranges that are not routed on the internet: 192.168.x.x (the most common at home; many routers use 192.168.1.1 or 192.168.0.1 for themselves), 10.x.x.x, and 172.16.x.x to 172.31.x.x. The router's NAT translates between these private addresses and the single public address the ISP provides. That is why your computer's ipconfig address (for example 192.168.1.50) is different from your public IP address.

Wireless signals do not stop at the front wall, so anyone nearby can receive them. The threats are unauthorised use of the connection, eavesdropping, attacks on devices inside the network, rogue access points, and denial of service.

The security protocols

WPA2 was the change that brought strong AES encryption; WPA's TKIP was a stopgap. WPA3-Personal replaces the password handshake with SAE (Simultaneous Authentication of Equals), which resists offline password guessing and protects past traffic even if the password later leaks. WPA3 has been mandatory for new Wi-Fi certified devices since July 2020, and Wi-Fi 6E and 7 on 6 GHz require it. Where some older devices cannot use WPA3, the WPA2/WPA3 transitional mode lets both connect. In any mode, avoid TKIP.

Each protocol has Personal and Enterprise modes. Personal uses one shared passphrase. Enterprise uses 802.1X to give each user their own credentials checked by a server, and is standard in business.

Hardening a home router

• Change the default administrator password straight away. Default router credentials are published online, and attackers try them automatically. (Australia's Cyber Security Act 2024 now allows mandatory security standards for smart devices, including banning universal default passwords, which is the same lesson made law.)
• Change the default Wi-Fi password printed on the sticker, since anyone who has seen the device has seen it. Use a long passphrase.
• Choose WPA3-Personal, or WPA2/WPA3 transitional, or WPA2 with AES if nothing else is possible.
• Change the network name (SSID) to something that does not identify the household, address or router model.
• Update the router's firmware, and turn on automatic updates if offered. Replace routers that no longer receive firmware updates.
• Turn off WPS (Wi-Fi Protected Setup), whose PIN method has been exploitable since 2011, unless actively pairing a device.
• Turn off remote management from the internet unless it is genuinely needed.
• Consider turning off UPnP, which lets devices open ports in the firewall automatically.
• Put visitors on a guest network, separate from the main one, with its own password and isolated from your devices. Many people put smart TVs, cameras and other internet of things devices on a separate network for the same reason.
• Review the connected devices list periodically.

Two measures are often recommended but give little real protection. Hiding the SSID stops the name from appearing in lists, but the network is still detectable with any analyser app, and it makes connecting harder for legitimate users. MAC address filtering is easily bypassed because MAC addresses can be copied, and modern phones use randomised MAC addresses by default. Neither replaces strong encryption and a strong password.

The same sequence works on almost any home router, whether it is configured through a web page or a phone app. Always follow the manufacturer's quick start guide for the specific model.

Check the delivery. Before installing anything, compare the box contents against the packing list: router, power supply, Ethernet cable, documentation, and any extras. If anything is missing or damaged, photograph the contents and contact the vendor straight away to arrange a replacement or credit.

Reset to factory settings if the router has been used before. With the router powered on, find the recessed Reset button on the back or base, press it with a straightened paperclip or a pen tip, and hold it for about 10 to 15 seconds (check the model's manual) until the lights flash or cycle. Release it and wait a minute or two until the power light is steady. All settings, including passwords, return to the defaults on the label.

Connect. Plug the router's WAN or internet port into the nbn connection box or modem (or the phone socket for a VDSL modem-router). Connect a computer to one of the LAN ports with an Ethernet cable for setup; a wired connection will not drop out when you change the Wi-Fi settings.

Log in to the management interface. Open a browser and go to the router's address from the label (commonly 192.168.1.1 or 192.168.0.1, or a name such as myrouter.local); some newer routers are set up through the manufacturer's app instead. Sign in with the default credentials on the label.

Change the administrator password. In the Administration, Management or Security section, set a strong new password, save, and sign in again with it to prove it works. Record it securely.

Configure the internet connection. Most nbn connections work automatically (IPoE and DHCP). For PPPoE, enter the ISP's username and password.

Set up the wireless networks. In the Wireless section, for each band (2.4 GHz, 5 GHz and, if present, 6 GHz): set the network name, choose the security mode (WPA3-Personal or WPA2/WPA3), and enter a strong passphrase. Save and apply. Set up a guest network if wanted.

Check the LAN settings. Confirm DHCP is on, and note the address range. Add DHCP reservations for printers or storage devices.

Update the firmware and set the router's time zone (for the NT, Darwin, UTC+09:30).

Back up the configuration if the router offers it, and record the settings.

Installing a wireless adapter

A desktop PC without built-in Wi-Fi needs a wireless adapter, usually a small USB adapter or a PCIe card:

• Check the adapter supports the router's Wi-Fi standard and bands, and the computer's operating system.
• For a USB adapter, plug it into a free USB port, ideally at the front or on a short extension cable, since ports at the back of a metal case surrounded by cables get poorer signal. For a PCIe card, power down, unplug, use antistatic precautions, and install the card in a free PCIe slot.
• Windows usually recognises it and installs a driver within a minute. If not, install the driver from the manufacturer's website.
• Confirm in Device Manager (right-click Start, Device Manager, Network adapters) that the adapter is listed without a yellow warning triangle.

Connecting to the network

Click the network icon on the taskbar, open the Wi-Fi list, choose the network name, tick Connect automatically, and enter the passphrase. On a phone or tablet, use Settings, Wi-Fi. Many routers also show a QR code that phones can scan to join.

Setting up a wireless printer

• Connect the printer to the Wi-Fi first, using its own control panel (setup wizard, choose the network, enter the passphrase) or the manufacturer's app. Ideally give it a DHCP reservation so its address does not change.
• Find the printer's IP address from its control panel or a printed network configuration page.
• On the computer, add the printer. Windows 11 often finds it automatically: Settings, Bluetooth & devices, Printers & scanners, Add device. If it does not appear, choose "Add manually", then "Add a printer using an IP address or hostname", and type the printer's address.
• Windows 11 can print to most current printers without installing any extra software, using Microsoft's built-in driver that works with the Mopria and IPP standards. For full features (tray options, scanning, ink levels), install the manufacturer's driver or software package from its support site. Microsoft announced in 2023 a gradual move away from distributing third-party printer drivers through Windows Update in favour of its built-in driver, and has adjusted the timeline since.
• Print a test page (printer's Properties, Print test page).

With devices connected, test from a computer:

• ipconfig shows the computer's IPv4 address, subnet mask and default gateway. An address in the router's range (such as 192.168.1.50) means DHCP worked. An address starting 169.254 means the computer did not get an address from the router.
• ping 192.168.1.1 tests the connection to the router. ping followed by the printer's IP address tests the path to the printer. "Reply from" lines with 0% loss mean the device answered; "Request timed out" means it did not (check that both devices are on the same network, and remember that some devices deliberately ignore ping).
• ping cdu.edu.au tests internet access and DNS together.
• arp -a lists the IP and MAC addresses of devices the computer has recently communicated with on the local network.
• The router's Connected devices (or Client list, or DHCP clients) page shows every device on the network, with names, IP addresses and MAC addresses. This is the easiest way to see who is connected, and to spot anything that should not be.
• Test security: confirm the old default admin password no longer works, that devices cannot join without the new passphrase, and that the guest network cannot reach the main network's devices.
• Walk the house with a phone or laptop to check signal strength in every room that needs coverage.

Before and after installation, confirm what support the client has:

• The manufacturer's warranty period and how claims are made (return to the retailer, return to base, or advance replacement). Find it on the manufacturer's support page for that model, along with the user manual, setup guide and firmware downloads.
• Under the Australian Consumer Law, consumers also have automatic consumer guarantees that goods will be of acceptable quality and fit for purpose, which apply regardless of, and in addition to, any manufacturer's warranty.
• ISP support for the connection, and any router the ISP supplied.

Leave the client with documentation: the equipment installed (make, model, serial numbers), the network names, where passwords are stored (never write them on the router), the security settings chosen, the IP address range and any reservations, the warranty details and support contacts, and any known issues.

In Australia, installing, maintaining or repairing telecommunications cabling on a customer's premises must be done by a registered cabler, under the Telecommunications Act 1997 and the rules the ACMA makes under it, currently the Telecommunications (Cabling Provider) Rules 2025. There are three categories of registration: open (the full range of cabling work), restricted (simpler work, typically in a single home or small office) and lift (an add-on for electrical workers in lifts). To hold registration, cablers complete approved training and register with an ACMA-accredited registrar.

For a home Wi-Fi installation, the line is clear in practice. Plugging pre-made patch leads between a router, modem and computers, and plugging equipment into existing wall sockets, does not need registration. Running cable through walls, ceilings or under floors, installing wall sockets or terminating cable does.

Home network installations carry real hazards:

• Electrical: check power leads and power boards for damage, never overload power boards, and do not open power supplies. Many workplaces require portable electrical equipment to be tested and tagged (AS/NZS 3760).
• Trip hazards from cables across walkways; route and secure them.
• Working at height when mounting access points: use a stable ladder correctly and have someone with you.
• Manual handling: lift boxes and equipment with correct technique, and get help with heavy items.
• Ceiling spaces, if cabling is involved (and that work belongs to a registered cabler): heat, which in the Top End can be extreme, insulation fibres, asbestos in older buildings, and electrical wiring.
• Sharp edges on equipment and packaging, and clutter in a home that is not your workplace. Ask the client about pets, children and access.
• Heat and hydration, especially working outdoors or in roof spaces in the NT.

Unused adapters and spare equipment should be stored as the manufacturer recommends: in their original packaging or antistatic bags, in a cool, dry place out of direct sunlight, labelled, and recorded in the inventory. The manufacturer's manual usually states the storage temperature and humidity range. Heat and humidity in the Top End shorten electronics' lives, so air-conditioned storage is worth it.

Packaging goes to recycling: cardboard and paper in recycling bins, and soft plastics through whatever collection is available locally. Old routers, adapters and cables are e-waste and must not go in general waste, because they contain lead, mercury and other hazardous materials. In Darwin, e-waste can be taken to the Shoal Bay transfer station; across Australia, the National Television and Computer Recycling Scheme provides free drop-off for computers and peripherals at participating sites, which can be found through Planet Ark's Recycling Near You. Batteries, particularly lithium-ion batteries, must never go in household bins because they start fires in bins, trucks and waste facilities; take them to a battery drop-off point such as those listed by B-cycle, the national battery stewardship scheme. For business equipment, wipe or destroy stored data first.

Two developments are worth knowing. Consumer routers and mesh systems increasingly use automated or AI-assisted features, choosing channels and bands, steering devices and flagging unusual behaviour through a phone app, which makes setup easier but means the router's management app and the account it uses become something to protect too. And the number of devices on a home network has grown well beyond computers and phones: TVs, speakers, cameras, doorbells, appliances, solar inverters. Each is a small computer that needs updates, a unique password and, ideally, its own network segment. The newer smart-home standard Matter, which runs over Wi-Fi and the low-power Thread protocol, is gradually making these devices more interoperable, and Australia's Cyber Security Act 2024 introduced the power to set minimum security standards for them.

The unit's teaching content is drawn from the CDU material held in the unit folder: the ICTSAS217 learning resource page on the CDU student site (last updated 11 May 2026), the ICTSAS217 Assessor Guide v4.4 (undated), the ICTSAS217 Student Unit Guide v1.1, the ICTSAS217 practical assessment instructions (undated), the ICTSAS217 pre-assessment validation report, the unit and assessment requirement documents for ICTSAS217 Release 1, and the ICT20120 practical observation checklist (February 2026). The unit is current at training.gov.au (no page date shown). Current-practice material was checked on 20 September 2026 against: the Wikipedia article on IEEE 802.11be-2024 (read 20 September 2026) for the Wi-Fi 7 certification date (8 January 2024), publication of the standard (22 July 2025) and the expected Wi-Fi 8 timeline; Network World on Wi-Fi 8's reliability focus (2026, exact date not shown); CyberShack on the ACMA's extension of 6 GHz Wi-Fi to 6585 MHz (2025, exact date not shown); nbn's media statement selecting Amazon's Project Kuiper (5 August 2025) and Aviation Week on the rebranding to Amazon Leo (2025); the ACMA's cabling registration guidance and its "ACMA cabling provider rules: pathways to cabling registration" (April 2025), which names the Telecommunications (Cabling Provider) Rules 2025; the City of Darwin e-waste page (no date shown); Planet Ark's Recycling Near You; and B-cycle (bcycle.com.au, no date shown). Wi-Fi protocol history, WPA3 requirements and the WPS vulnerability are widely documented by the Wi-Fi Alliance and security researchers; the building-material signal losses are typical published values that vary by construction.