How do wireless routers transmit data?
The primary purpose of a wireless router is to share an internet connection in the home, but it can also transfer data from one computer to another or to a peripheral device such as a printer. Wireless routers and any computers connected to the network use a transmitter and a receiver to send data back and forth. Information is sent via radio waves, usually at a frequency of 2.4GHz, though sometimes the 3.6GHz and 5GHz bands are used. The wireless router has its own DNS (domain name system) registry, so it can process requests to view certain websites or pages. Once you enter the URL of a website you wish to visit into the address bar on your computer's browser, the router uses its DNS registry to convert it into an IP (internet protocol) address to direct you to the correct site.
Many new computers come with wireless networking functions as standard, but older laptops and desktop PCs may not and will require further hardware such as a USB dongle or a PCMCIA (Personal Computer Memory Card International Association) card to connect. These can be picked up for as little as £15.
 
What are the antennae for?
These aren't just for show - they really do play a part in relaying signals from the router to your computers and vice versa. If you're having a problem with a slow connection then you should try setting the antennae to a different position to see if this helps. If it doesn't, you can buy devices that extend the range of your wireless network such as the dLAN Wireless Extender Starter Kit from Devolo (www.devolo.co.uk), which costs around £70. It works by taking advantage of your home's electricity circuits - you plug one of the extender devices into a wall socket and connect it to your wireless router. Then you can plug a second device into another wall socket elsewhere in the house, creating a new wireless access point.
 
Can I connect wired devices to a wireless router?
Yes - and if your main computer is within a short distance of your wireless router you should definitely connect the two devices using an Ethernet cable to a spare LAN (local area network) port on the router. This will increase the security of the connection between the PC and the router, as well as the speed at which the two can send data to each other.
USB ports on your router let you connect other devices, such as a NAS (network-attached storage) devices and printers, so you can share the storage and printing facilities between all the computers on your network.
 
Which wireless standard should I use?
There are several standards, all beginning with the code IEEE802.11. The first commonly used standard was 802.11b, which has a maximum data transfer speed of 11Mbps. The 802.11a standard, which was released at the same time, offered faster data transfers, but didn't have as good a range. A few years later, the 802.11g standard emerged, which offered the 54Mbps data transfer of 802.11a with the range of 802.11b. It was also backwards compatible to work with the 802.11b standard, but has since been superseded by the 802.11n standard.
Although this standard hasn't officially been ratified yet by the IEEE (Institute of Electrical Electronics Engineers), most new wireless routers support it. In addition to much higher transfer speeds - up to 600Mbps (in theory, at least) - 802.11n also uses MIMO (multiple input, multiple output) technology, which allows for multiple antennae in both the transmitter and receiver, improving the reliability of the communication between the two. If you are buying a new router, look for one that supports 802.11n, which is also backwards compatible with the other more common standards.
 
Are there any associated health risks?
Though some scare stories claimed that the radio waves used in Wi-Fi could cause cancer, several of the scientists pushing the theory, such as Professor Olle Johansson of the Karolinska Institute in Sweden, have since been discredited. The UK's Health Protection Agency (HPA) has passed Wi-Fi equipment as safe to use in schools, saying that radio frequency exposures from wireless networks are likely to be less than those from mobile phones.
 
HOW TO SECURE YOUR WIRELESS ROUTER
The first thing you should do when setting up your wireless network is change the name of your router as well as the default login name and password. If a criminal knows the model name of your router, there is a good chance they can find out what the default login and password are with a quick web search. If they can do this, then they'll be able to use the connection for their own purposes or even alter the DNS to redirect you to websites containing malware.
Secondly, you should ensure you choose an appropriate level of encryption. WEP (Wired Equivalent Privacy) has been shown to be easily cracked and should be avoided if possible. WPA (Wi-Fi Protected Access) is a more secure method though not entirely uncrackable, but WPA II, the latest generation of this encryption standard, is recommended. Any device that connects to your wireless network - whether a laptop, mobile phone or media-streaming device - will need to support WPA II as well. Some older gadgets will not be compatible.