Wireless networking demystified

The Wi-Fi 802.11n logo. (Credit: Wi-Fi Alliance)

The concept of wireless networking itself isn't that hard — your device can communicate with your router or access point without using wires, allowing you to roam freely.

Setting up a wireless network in the home though is quite possibly the most daunting aspect of networking for consumers. While it's slowly getting easier, there's still a number of standards and encryption mechanisms you need to deal with before you get the optimal solution — we're not in a "push button and it works" type scenario just yet.

Wireless isn't as fast as good old-fashioned Ethernet cable when it comes to transferring data, but it's still more than fast enough for general internet use and streaming standard-definition video to your laptop or wireless enabled device (like an iPod Touch) as you wander around the house. Plus, if you're the type that doesn't like cables criss-crossing their house, short of building them into the walls, a combination of wireless and power line networking is likely the best choice for you.

802.What?

Wireless networking, or Wi-Fi, mostly comes as part of the 802.11 standard. There are four flavours currently on the market: 802.11a, 802.11b, 802.11g and 802.11n. Most laptops these days are equipped with 802.11n network capability, and even if you own an older laptop without wireless, it's easy enough to pick up an expansion card that will do the job for you. While 802.11n theoretically offers greater speed and range than the previous 802.11g standard, 802.11g is still the most used format in the consumer market. This will change — although there's still plenty of G equipment on the market, with the N standard finally being ratified in September 2009 we expect the switch-over to be reasonably rapid.

The good news is network adapters are backwards compatible, meaning an 802.11g certified device will quite happily chat to an 802.11b device, and an 802.11n device will talk to both g and n, and as a bonus it will also communicate with 802.11a (which some older g or b devices will not). These all work in the 2.4GHz range, the same frequency that your cordless phone, microwave and several other devices work at, meaning they may suffer from interference.

The odd one out is 802.11a, which operates in the 5GHz band, making it good where high levels of interference are present. While 802.11a enjoyed a good life in the corporate world as a result, it will likely be rapidly supplanted 802.11n, which allows dual-band access — meaning it can operate in both the 2.4GHz and 5GHz space simultaneously.

Wireless outside the home

Hotspots
Wireless also brings to life the concept of the hot spot — a public area where you can get access to free internet, thanks to a wireless router hooked up to a net connection. These are often set up around big coffee chains like Starbucks, as well as a large number of McDonalds stores. City-wide, wireless is being trialled in many places, and in conjunction with femtocells, 3G and WiMax the all-pervasive internet might become reality. There's a decent list of hot spots listed over at Whirlpool (although it may not be up-to-date), and you may want to check out free-hotspot.com and wififreespot.com as well.

3G and mobile broadband
The iPhone changed the game for mobile internet use, so it's worth mentioning the 3G mobile network as an option. Most smartphones these days will happily switch between your local Wi-Fi network when you're home, and your 3G mobile network when you're out of range. This means you can always be online — just be aware of the different cost structure when your phone roams between the different networks — costs are still quite high on 3G networks, with low data allowances.

A corollary of this is mobile broadband — which is sometimes referred to as a Wireless Wide Area Network, or WWAN. Coming either built into your laptop (which requires a SIM card) or as a USB adapter, these devices simply get your PC on the same 3G network your phone uses. Some mobile phone providers are even offering laptops for free when you connect to a mobile broadband plan.

You'll find the plans are different for these than internet access on your phone though, so make sure to pay attention to the pricing details. Muddying the water a bit is the concept of "tethering" — using your phone as a WWAN modem for your PC, assuming the handset supports it. In this case, you'll be paying phone data rates for your PC to access the internet over the 3G network — but it's a handy in-lieu technique for getting internet access at home while you're waiting for your ADSL or cable modem to be installed.

WiMax
You might have heard about WiMax — this is a high range wireless standard that's mostly used for broadband internet access where ADSL or cable can't be rolled out, mainly targeting rural areas — although it's being looked into as a 3G competitor or replacement in cities as well. There are a few companies investing in WiMax at the moment such as Energy Australia and Unwired, and Intel is a big supporter of the standard, suggesting it should be used to support whomever misses out on the National Broadband Network. At the moment, it's not very widespread, and you'll need a WiMax adapter to be able to receive the signal — something that's nowhere near as prolific as its 802.11 counterparts. Watch this space.

The Bluetooth logo.
(Credit: Bluetooth SIG)

What is Bluetooth?

Usually used for short range, one-to-one connections, Bluetooth nonetheless has a range of anywhere up to 100 metres (depending on the class of device it is, and how much power is being pumped through), and tends to be used for transferring files from PDAs/mobile phones to other Bluetooth enabled devices (such as your laptop), and for wireless headsets, graphics tablets, printers, cameras, keyboards and mice. Short range wireless connections such as Bluetooth form what is often called a Personal Area Network, or PAN.