Tuesday, 9 June 2015

How to double your Wi-Fi speed

How to double your W-Fi speed

Annoyed by a sluggish wireless connection? Darien Graham-Smith explains how to spot what’s causing the problems – and how to solve them

If your connection is crawling along, the first question to ask is whether it’s really the network that’s to blame. The true culprit could be a specific program or device clogging up your network – perhaps a backup job beaming terabytes of data to your NAS box, or an infected device that’s been subsumed into a botnet, and is now, without your knowledge, flooding out malicious datagrams to destinations all around the world.


With free software such as Wireshark (wireshark.org), you can inspect all the data packets on your network as they fly through the air, and easily discover whether one device is taking up more than its fair share of bandwidth. Your router’s web-based administration interface may also offer reports and logs: the way you access these will diˆffer between models and manufacturers, but they’re well worth looking at since they’ll also include activity from wired clients.

Don’t assume that you know about every device on your network: if your network is open, or has a guessable password, your neighbours or others could be leeching bandwidth and hoping you won’t notice. You can boot them oˆff, or use your router’s QoS settings to prioritise the traŒ c that’s especially important to you.

If all that sounds like too much hassle, try simply switching offˆ your network connected devices one by one, and keep checking network speed as you go. For obvious reasons, an online speed-tester isn’t the right tool for this, as results will be limited by the speed of your internet connection rather than your domestic wireless network. Don’t trust the wireless link speed reported by Windows either: this gives an idea of the theoretical throughput of your wireless connection, but if you’re interested in real-world performance, there’s no substitute for copying files back and forth between devices. If switching off a spare PC causes things to suddenly start zipping along, it suggests a little housekeeping may be all that’s needed to give your wireless network a boost.

CHANGING THE CHANNEL


If you accepted the default settings when installing your router, your wireless network is probably sending and receiving data in the 2.4GHz band, and specifically on channel 1, 6 or 11. This means packets are broadcast and received over a fairly wide radio band, centred on 2,412MHz, 2,437MHz or 2,462MHz.

These frequencies have been a standard part of the 802.11 wireless protocol since its introduction in 1997, so using them as defaults ensures that pretty much every Wi-Fi device in your home (and, indeed, in the world) should be able to talk to the router.

The downside is that if you live in a dense urban area, such as a block of flats, your neighbours’ networks will be using these frequencies too, resulting in interference that slows down the connection for everyone. Other electrical appliances such as cordless phones and wireless video extenders may use these channels as well. And while microwave ovens are normally well shielded, these too can generate radio “noise” at frequencies in the 2.4GHz range, which is highly disruptive to radio communications.

The simplest answer is to switch your network to a diˆfferent frequency. Your router’s settings page should provide a dropdown allowing you to switch to a diˆfferent channel within the 2.4GHz band – they’re numbered from 1 to 13. Experiment by changing this to see whether one end of the spectrum provides a better connection than the other: your devices should automatically rediscover the network and reconnect soon after you change the channel.

If you prefer a more methodical approach, use a free tool such as NirSoft’s Wifi InfoView (tinyurl.com/or9b62v), or a smartphone app such as Wifi Analyzer for Android (pcpro.link/249wifianalyzer). These will survey all the wireless networks within range and their relative signal strengths, so you can avoid them as far as possible. Remember, though, that such tools won’t show up interference from other sources; if all your neighbours are avoiding a particular channel, there may be a reason for this.

BAND ON THE RUN


If switching channels doesn’t help, consider hopping to a different frequency band altogether. The 5GHz Wi-Fi band came into use in 2009 as part of the 802.11n standard, and since there’s less interference in this band, it may provide better performance. (Strictly speaking, the 5GHz band had in fact been introduced a decade earlier in the old 802.11a standard, but this never really became popular.)

Some older devices may not support 5GHz, but this isn’t necessarily a showstopper: most routers that support a 5GHz wireless network will let you run it alongside a regular 2.4GHz network. This does mean that you’ll have two separate SSIDs to manage, which complicates the job of administering things, especially if you want to ensure your devices connect to the right one.

A second possible issue with 5GHz is that a higher frequency means lesser penetration, so you’re less likely to experience interference from three doors down – but, by the same token, if you’re trying to extend your network through an interior wall or two, you may find that the drop-off at 5GHz is barely preferable to the interference at 2.4GHz.

EXTENDING RANGE


Even if there’s nothing but clear air between your router and its Wi-Fi clients, location can have a big effect on signal quality, since wireless links (like all radio transmissions) grow weaker over distance. If you want to improve the quality of a wireless signal far from your router – such as in a summerhouse at the bottom of your garden – a simple option is to invest in a wireless repeater or a range extender, which you can position between the two stations to retransmit packets back and forth at full strength.

It’s worth noting that repeaters and extenders do different jobs. A repeater acts as a rebroadcasting station for your router, and is effectively invisible to connecting clients. A range extender, on the other hand, operates a wireless network of its own, and acts as a bridge between devices connected to this network and your home LAN.

If you want to save money, it’s possible to set up an old router as a repeater or range extender, although you may need to dive into technical settings to make it work, and older hardware may not support the latest high-speed connection technologies. It’s also possible to configure a PC or Mac to act as an extender; of course, this isn’t a particularly power-effcient solution, unless you’re using the system for something else at the same time.

Whichever approach you choose, the involvement of more hardware and potentially more packets flying through the air means that network performance might not be as fast as it would be if you were able to move your PC closer to the router. But it should certainly be better than an unboosted long-range connection.

AIMING AND UPGRADING YOUR ANTENNAS


We’ve mentioned that walls affect signal strength, which in turn hinders your connection speed. In fact, almost everything in your home has an effect on the throughput of your wireless network: radio transmissions bounce off furniture and other obstructions, so even when you’re in the same room as your router, there will be pockets of interference.

There’s no way around this, but you can make a difference by moving your router, or adjusting the orientation of its antennas. One useful ploy is to position your router away from the floor, and as far from walls as is practical; otherwise, it will be surrounded by reflected signals. When it comes to finer positioning, you can use Wifi InfoView, mentioned above, to test the strength of the signal in a given part of your home, and experiment with repositioning the router (or other items around your home) to see if any particular arrangement improves matters.

You can also try to upgrade your antenna to give it a better reach. You’ll find various tutorials online showing how to build a reflector out of an old beer can, or out of tinfoil, which can help focus the signal towards your devices. If you don’t mind spending a bit of money, you can replace your router’s antennas altogether with a larger aerial on a cable. These are often advertised as “high gain”, but the benefit isn’t really increased signal strength – rather it’s the fact that it’s easy to position such an antenna wherever you want, while keeping your router tucked away somewhere more convenient.

HACKING YOUR ROUTER


Another way to make the signal from your router carry further is to make it transmit more strongly. Typically, a domestic router will ship with a fixed transmission power of 70mW, and while you may be able to turn this down (to make it harder for people to piggyback on your network from afar), you can’t normally turn it up.

For the technically inclined, however, all things are possible. On a huge number of routers – especially older 802.11n models – it’s possible to replace the built-in firmware with the free, open-source DD-WRT. This provides access to a wide range of settings that aren’t offered directly by the manufacturer, including the ability to ramp up the signal strength all the way to 250mW.

Of course, there’s no such thing as a free lunch. Flashing third-party firmware onto a router carries risks – and good luck getting the manufacturer to help you if anything goes wrong. Bear in mind, too, that you’re tweaking only the strength of the signal from the router – your mobile devices will still be transmitting at their default signal strengths, so this won’t necessarily do much for transfer speeds between them.

A final, rather important point is that turning up the signal strength to maximum may cause your router to overheat and crash. So if you want to try this hack, keep your router somewhere cool, and proceed with caution.

UPGRADE TO 802.11AC


The measures we’ve mentioned so far aim to squeeze the best possible performance out of your existing wireless network, but if you’re not already using the latest 802.11ac technology, upgrading is likely to be the single most eƒffective thing you can do to accelerate your network. Where 802.11n has a theoretical maximum connection speed of 600Mbits/sec, the latest 802.11ac routers push the limit up to 2.3Gbits/sec.

Of course, you shouldn’t expect to see those speeds in real-world use. These figures assume perfectly matched hardware in perfect communication conditions, which you won’t get even if you position your laptop directly on top of the router. All the same, you can expect to see a significant boost simply from making the switch.

Buying a state-of-the-art router costs money – our current A-List favourite, the superfast Netgear R7500 Nighthawk X4, won’t leave you much change from $400. And only laptops and other devices that support the full speeds of 802.11ac will benefit. Most recent models will, but check before you invest.

IS WIRELESS THE ANSWER?


Our final recommendation may sound like a trick question: “What’s the best way to improve your wireless performance? Don’t use wireless.” But if you want to hook up a PC to a router located at the opposite end of your home, there may be better options than Wi-Fi. The obvious alternative is powerline networking, which lets you run a wired Ethernet connection between two or more domestic power sockets, with no need to trail messy cables down the corridor.

It’s not the perfect solution, however. Not all devices support wired Ethernet – smartphones and tablets certainly don’t. What’s more, mains circuits are inherently very noisy, and the signal degrades sharply over distance. Current homeplugs may advertise a maximum transfer speed of 300Mbits/sec over a Gigabit Ethernet connection, but if you’re connecting across several rooms then 60Mbits/sec is a more realistic expectation.

A compromise might be to invest in a powerline-based wireless extender. This lets you run a powerline connection from your router to another part of the house, and host a wireless network from there. The powerline run won’t be as fast as a direct Ethernet connection, but if the location of your phone socket obliges your router to reside in a remote corner of the house, such an approach might be your best option.