Set-up
Most modem/routers consist of a box with one port on the back that connects to your cable or phone line - usually labelled 'WAN' - and around four other ports that look the same, but that are labelled 'LAN' and designed to allow you to connect devices to the router using an Ethernet cable.
Some (though not all) routers also have external antennae that give you a bit of flexibility in how they're positioned. The degree to which adjusting the antennae affects the signal's strength depends on the router. If your router has internal antennae, it may use a technology called 'beamforming' that increases the power of the signal in the direction of connected devices.
Setting up the modem/router is as simple as plugging it into a mains power outlet and then connecting the supplied cable to your cable or phone line. In most cases, the SSID (Wi-Fi network name) and default password for the router will be on a sticky label on its underside. If not, it should have been supplied to you separately.
Once you have the SSID and password, click on the Wi-Fi symbol in your Mac's menu bar and select the SSID from the menu. If it's not there, select Join Other Network and type in the SSID. Type in the default password, and you should be connected in a few seconds. The procedure on an iOS device is similar; just select Wi-Fi from the Settings app.
If you don't have an Apple router (which is configured using AirPort Utility) you'll probably have been supplied with an internal IP address for the router, usually in the form 192.168.x.x, along with a username and password. Type that into the address bar in your browser and log in.
Settings screens for routers vary, but somewhere there will be a W-Fi network menu. Select it and change the default SSID and password to something that's memorable to you. Also, change the admin username and password for the router settings. It's worth taking time to familiarise yourself with the options available.
Router location
Whether we have cable broadband or DSL, most of us have one box that doubles as a modem and router. Its location will be dictated by the location of your phone or cable point, and so you'll be limited in how far you can move it. Nevertheless, you should, as far as possible, place it well off the floor - either wall-mounted or on a desk or shelf, and as far from the corner of the room as possible.
Wireless routers broadcast omni-directionally, and the closer you place yours to an obstacle like a brick wall, the more you'll restrict its signal. Ideally, you'd have it floating in mid-air just below the ceiling in the room that is closest to the centre of the house! Place it as close to that point as you're able.
If your telephone or cable point is in the living room and your study is at the other end of the house, you might have to extend the range of your network or create a new one that has a wired connection to the router - we'll discuss both of these options later.
Surroundings
As we've said, wireless signals are obstructed by walls and other obstacles. Try and keep the area immediately around the router clear of sofas, bookcases, and anything else that might block the signal. If your telephone or cable point is close to the ground in the corner of a room, buy yourself a longer cable and give yourself more flexibility in where you can position the router. If that's not possible, consider buying a separate wireless router and connecting it to the modem/router with an Ethernet cable.
Finally, wireless signals tend to be stronger below the router than above it, so when placing the router, the higher the better. If you plan to use the same one upstairs and downstairs, consider placing the modem/router upstairs, if possible.
Check the signal
Both Lion and Mountain Lion have tools that allow you to monitor wireless performance, but they're hidden away in the System/Library/CoreServices directory. You'll need to use Go To Folder (Command+Shift+G) in the Finder's Go menu to access the directory. In Lion, the tool is called Wi-Fi Diagnostics; in Mountain Lion, it's Wireless Diagnostics.
When you've found it, launch it and select Monitor Performance. In Lion, all you need to do is click Continue. In Mountain Lion, click the Window menu and select Utilities (Command+2). Click the Performance tab. Depending on which version you're using, you'll see one or two graphs; both display the signal-to-noise ratio of the wireless signal. You can monitor the effect of any changes you make to router location.
Your aim should be to maximise the difference between signal strength and noise, but focusing on reducing noise. Why? Because most of the time, your wireless network is a direct conduit to your internet connection, and it's the internet connection that acts as a bottleneck, not the signal strength of your wireless network. An unacceptably high level of noise, on the other hand, can lead to dropped packets, poor performance and dropped connections.
Using Wireless Diagnostics is useful if you use AirPlay to stream audio and video from your Mac or iOS device to an Apple TV or AirPlay speaker, particularly if you mirror apps from an iOS device.
Extending Wi-Fi
Increase the effective range of your wireless network with these solutions
There are several ways in which you can extend a wireless network. The simplest - and potentially most effective - is to move your router. If it's positioned in the corner of a room at one end of the house, near the floor, move it higher and towards the middle of the house. If this isn't possible because your router is also your DSL or cable modem and needs to be close to a telephone or cable point, consider buying a separate router, and, ideally, connecting it to the modem/router by Ethernet.
Equally, if your modem/router is more than a couple of years old, the chances are that it uses an older Wi-Fi standard than many of your devices. If you have an 802.11b or g router and have Macs and iOS devices that support 802.11g (or even 802.11ac), then upgrading your router, while not extending the range of your network significantly, will give you higher data throughput at the outer limits of the Wi-Fi signal.
If you choose this route, you'll need to set your new router to 'bridge mode'. This effectively switches off its DHCP server and stops it handing out IP addresses, turning it into purely a wireless access point. That prevents it from conflicting with the router in your modem/router.
Antennae upgrade
Another option for extending your network is to upgrade the antennae. If your router has external antennae, you can replace them with high-gain antennae such as those made by Hawking, Edimax and D-Link. Alternatively, you can even create your own parabolic reflector that attaches to the antennae and bounces the signal towards where your devices are located. The final option is a wireless repeater or extender that sits at the outer edge of your Wi-Fi network and re-broadcasts the signal, allowing it to travel further.
There are a couple of problems, however. Firstly, Wi-Fi signals are omni-directional, meaning that the re-broadcast signal from the repeater will not only extend your network, but will also be transmitted back towards your router, potentially interfering with the signal and degrading it. This is a particular problem on the 2.4GHz channel. Also, to be effective, a repeater should be situated close to the router, which somewhat defeats the object.
Finally, a wireless distribution system (WDS) - used by routers to link to each other wirelessly - doubles the number of 'hops' required to send and receive data and, because the repeater must use half of its data capacity to connect to the router and the other half to connect to devices, its throughput is significantly reduced. If you can't move your modem/router, the best option is a new router set to bridge mode, and connected by Ethernet.
Powerline networking
Why run extra cabling when you can use what's already in your walls?
Powerline networking uses the mains power cables in your house or office to carry data. It's a very effective way of installing a wired network without having to install Cat 5 cable, with all the disruption and expense that entails.
At its simplest, a powerline network consists of one adapter plugged into a power socket with an Ethernet cable running from it to a LAN port on your modem/router. Another adapter is plugged in to a power socket close to your computer, printer or other device that needs a wired connection, and an Ethernet cable runs from it to your computer or device.
Equipment is usually bought initially in the form of a kit that includes two adapters and two cables, and is then supplemented with the purchase of additional adapters as and when they're needed. While data can be transmitted anywhere within your home or office, it's secure because it's physically prevented from straying next door, in the same way as you can't accidentally use your neighbour's electricity supply to run your kettle.
In addition, there are no issues with signal strength falling off the further you move from the router, and noise is minimal (though in older properties with ancient wiring, you might have a problem).
Power up
Powerline adapters come in various shapes and sizes and are differentiated in two ways. The first is data throughput. Early powerline adapters were limited to data transfer rates measured in mere tens of megabits per second. Nowadays, most adaptors have throughputs of 200Mbits/ sec or 500Mbits/sec.
The second way in which powerline adapters differ is in their physical features. One of the biggest limitations of a powerline network is that it occupies one power outlet for every adapter. If you're short of sockets, that can be a problem. Some adapters now have passthrough sockets so that you don't lose the power outlet and can plug a lamp, TV or whatever into the powerline adapter.
Most adapters have one Ethernet port, but there are some on the market with up to four sockets, which might be useful if you have, say, a computer and printer close to one another; you can connect both to the same adapter.
Finally, most powerline adapters have the plug physically connected to the adapter. But some multi-port adapters take the form of a small box into which you connect a power lead. These are bulkier, but come with the advantage that they won't block a neighbouring plug socket in a power strip (though you shouldn't really plug a powerline adapter into a multi-point strip, since those multiple sockets can introduce noise and degrade the signal). Well-known brands of adapters include Belkin, D-Link, devolo and Netgear.
Choosing your router
It's worth not just sticking with whatever router your ISP supplied; here's why
This is the point in the feature at which we're supposed to take you step-by-step through all the things you should consider when buying a new wireless router. And we will, but before we do that, let's be clear: if you're a Mac user with an iPad, iPhone, or iPod touch and those are the only devices you're going to connect to a wireless router, there's really only one game in town: AirPort Extreme. OK, two games in town: if you want the extra features, consider a Time Capsule too.
The reasons are many. Firstly, when hooking up wireless devices, sticking to one vendor is generally a good idea (WDS implementation varies between vendors). And while we can't guarantee that the original manufacturer of the wireless chip inside the latest AirPort Extreme is the same as the one in your Mac or iOS device, we can be pretty damn sure that Apple has tested it exhaustively for compatibility with (at the very least) its current product line-up.
Secondly, AirPort Extreme supports the latest 802.11ac standard, meaning that, while you might not have any 802.11ac devices currently, it's future-proofed. 802.11ac has a theoretical maximum throughput of 1,300Mbps, and while you won't get anything like that - particularly if you're connecting g and n devices - its support for 80MHz wideband means that when you do eventually acquire ac devices, they'll have plenty of bandwidth.
AirPort Extreme also supports beamforming, the technology that ensures the wireless signal is strongest exactly where you need it. And it looks kinda pretty too.
If you can't stretch to an AirPort Extreme, consider AirPort Express. It's 802.11n compliant, and operates on both 5GHz and 2.4GHz. Plug its WAN port into a LAN port on your modem/ router, or connect it using powerline networking, and you can use it to surf the internet from places your modem/router won't reach, or to upgrade an 802.11g router to 802.11n.
Outside the Apple universe, there are numerous things to consider. If you want a wireless router purely to connect a laptop and a couple of other devices to the internet, forget about data throughput. As we explain in the WAN section, your internet connection is the bottleneck there, and upgrading your wireless network won't help.
What might assist matters is a dual-band router; if you have devices that support 802.11n, look for a router that supports the n standard. Separating 2.4GHz and 5GHz devices reduces interference and improves the performance of your network. But avoid routers that support only 5GHz - unless you know you'll never have to connect a 2.4GHz device.
For flexibility, a router with four Ethernet (preferably gigabit rather than 100 Base-T) ports will allow you to connect devices directly with Ethernet cables. This might be more important than you think. If, for example, you have a Virgin Media TiVo box and want to use the Virgin Media Anywhere iOS app to control it, the box must be connected to your network by cable. Similarly, if you have a set-top box, smart TV, or games console that doesn't have built-in wireless capability, or supports only b or g, you may be better off hooking it up to your network directly (assuming it has an Ethernet port) rather than buying a separate Wi-Fi adaptor.
Talking of ports, some routers, like AirPort Extreme, have a USB socket. This is good. You can either hook up a printer and make it accessible to Macs and PCs on the network, or attach a hard drive and share its files over the network. We'd recommend a dedicated NAS box, not least for the extra features it offers, if you plan to share files on a network, but a USB hard drive attached to a router is great for occasional use.
The ability to create a guest network is a pretty clever feature, too. Did we mention that AirPort Extreme can do that? A guest network allows you to give visitors to your home or office wireless access to the internet, without letting them roam freely over the rest of your network.
Support for WPA2 security should be a given, but double-check to make sure. And a decent router should also have a WPS (Wi-Fi protected set-up) button to allow you to connect compatible devices without too much fiddling.
Internal or external antennae? Excellent question, glad you asked: most routers now come with the antennae hidden away inside the case. That, of course, makes them more aesthetically appealing - a not-insignificant consideration, given what we've already said about placement.
Routers with external antennae, however, do have a couple of advantages. The first is that you can adjust an antenna to improve the signal, though in reality this is likely to make little difference. The second is that you can replace the antennae with third-party versions; these might allow you to place them away from the router, say, higher up, and improve the signal.
That's an additional expense, however, and again, not likely to improve matters a great deal, so don't fixate on getting a router with its antennae on the outside.
Don't ignore travel routers. If your purpose in buying a router is to create a bridged wireless network or to act as an access point to an internet connection rather than to connect multiple devices using Ethernet, it might be worth considering a travel router. For obvious reasons, these boxes are smaller than regular routers, and typically have fewer Ethernet ports and smaller antennae. But they're very capable and have the advantage that they can be taken with you, so if you find yourself in a hotel room with wired internet access you can create your own in-room wireless network.
The need for speed
How fast the internet is piped into your home depends on many factors
Every router has a port labelled 'WAN', which stands for Wide Area Network. It's the port used to plug into your phone line or cable socket to connect it to the internet. For all our attempts to maximise the performance of your network, if all you do with it is connect to the internet (rather than, say, stream video around the house or mirror an iPad over AirPlay), it's that connection that will be the bottleneck.
While 802.11n has a theoretical maximum throughput of 450Mbps (that's megabits; equivalent to 37.5 megabytes/sec) your internet connection is likely to have a maximum data rate of somewhere between 2Mbps and 120Mbps. Most of us have connections at the bottom end of that range, and like Wi-Fi, the real-world figure is much lower than the theoretical maximum. You can check the actual speed of your internet connection by heading tospeedtest.net and running the test there; it's a good way of discovering how close to your ISP's advertised rate you're actually getting. It compiles results from users' tests and from those puts together league tables of ISPs. So if you're not happy with yours, you can look at which ISPs are delivering data throughput that more closely resembles their advertised rate.
It's worth doing the test at different times of day to see how the rate varies. Your internet connection is, in reality, 'shared' with your neighbours. That is to say, that if lots of people in your street use, for example, a BT or Virgin Media connection, you'll be effectively sharing bandwidth with them.
That's known as contention. Contention ratio - the degree to which bandwidth is shared - varies from ISP to ISP. But it it's likely that your internet connection will slow significantly at peak times, such as the evening, when your neighbours are also online.
There's another factor that affects your internet connection speed: traffic shaping or traffic management. Most ISPs use some form of management to limit the effect the most bandwidth-hungry users have on their network. Virgin Media, for example, throttles users' connections at peak times if they exceed a certain figure for downloads during a specified period.
It also limits the speed of traffic to and from newsgroups and peer-to-peer networks during peak times, but claims that this only affects five per cent of its customers. Other ISPs place limits on how much you can download in a month (which should be clearly stated in your contract) or, like Virgin, limit speeds for some users during peak times.
