Computers and computing can be somewhat bewildering for the novice. The terminology can be somewhat technical and ‘geeky’ at times. In view of this, I thought it would be a good idea to have a ‘Plain English’ guide, so here it is.
Sometimes written as WiFi, this is really a trademark of the Wi-Fi Alliance to be used with products and devices that have been approved and meet the required standards for wireless products and devices. The standard is known as IEEE 802.11 and so the next definition is for IEEE. Wireless products and devices basically use radio technology to broadcast and receive signals between devices.The actual name ‘Wi-Fi’ doesn’t actually stand for anything, but was a marketing term coined to be more catchy than IEEE 802.11!
The original standard and specification for Wi-Fi was proposed in 1980 and in May 1985 the U.S Federal Communications Commission made available several radio bands for unlicensed use. Other countries followed its lead and 1991 the foundation of what we now know as IEEE 802.11 was established by NCT/AT&T in Holland.
An interesting story is that it was actually CISRO (Commonwealth Scientific and Industrial Research Organisation), an Australian Government scientific body, that obtained the first patent for its version of wireless data transfer technology in 1192. They successfully obtained a similar patent in the US in 1996, essentially for the mathematical formulae used in Wi-Fi. In 2000, they successfully gave the first practical demonstration of the world’s first wireless LAN (Local Area Network). In April 2009, they successfully sued Intel, Microsoft, HP and Dell for $250 million for infringing their patents.
The advantage of Wi-Fi is that unlike wired networks, you don’t need wires! So, you can use your laptop (for example) at some distance from your router without needing to be physically tethered by a cable (Ethernet – see below) to your router. This means you can work on your laptop in the garden whilst the router sits in the house as normal. However, you can only does this if you a wireless router and a wireless adapter or internal wireless card in your laptop. However, most routers these days are wireless and most laptops come with an internal wireless card.
There are some differences between how Wi-Fi is implemented in different countries. The bandwidth for Wi-Fi signals is divided into channels. In the U.S. there are only 11 channels (1 to 11) whilst in most of Europe there are 13 (1 to 13). In Japan there are 14. However, to further complicate matters, the 2.4 GHz band used by most Wi-Fi devices, there are actually 5 channels. This means that of the channels in the U.S. there are only three channels which do not overlap (1, 6 & 11), whilst in Europe most countries have 4 (1, 5, 9 & 13)! You can change what channel your wireless router operates on by logging into the configuration page in a browser window. This is one way to minimise interference from adjacent networks operating on the same channel. This is quite common as most routers come with a default setting out of the box and so there’s a good chance your neighbours will all have their routers using the same channel as yours. In this situation it best to try each of the non-overlapping channels to see which gives the best signal.
IEEE 802.11 is a set of standards carrying out wireless local area network (WLAN) computer communication in the 2.4, 3.6 and 5 GHz frequency bands. They are created and maintained by the IEEE LAN/MAN Standards Committee (IEEE 802). The base current version of the standard is IEEE 802.11-2007.
The Institute of Electrical and Electronics Engineers or IEEE (read I-Triple-E) is an international non-profit, professional organization for the advancement of technology related to electricity. It has the most members of any technical professional organization in the world, with more than 395,000 members in around 150 countries. [credit:Wikipedia]
Originally established in 1963 following the merger of two organisations, Institute of Radio Engineers (IRE, founded 1912) and the American Institute of Electrical Engineers (AIEE, founded 1884), it publishes the standards for Wi-Fi but does not test actual devices. This led to the forming of the non-profit Wi-Fi Alliance in 1999 to enforce standards and to promote the wider use of wireless local area network technology. An important part of its role is to ensure the backward compatibility of devices whenever the standard is revised and updated. This means that if you use say a 802.11n router it will still work with your old 802.11g adapter.
You will see some devices are labeled as 802.11 b/g, some as 802.11a/b/g and some as 802.11 a/b/g/n. This refers to the standards that it is compatible with and as mentioned above, a 802.11 a/b/g/n device should work with a 802.11 b/g device. Some devices may simply be labeled on the box as Wireless G or Wireless N or MIMO. Wireless G devices are 802.11 a/b/g devices and Wireless N and MIMO devices are 802.11a/b/g/n devices.
As well as using power (electricity), wireless devices signal output (the strength of the radio waves transmitted in effect) is measured in terms of decibels over a reference power emitted by an isotropic radiator (of radio waves) with an equivalent signal strength. What this means is that different kinds of antenna radiate their signals in different patterns. Some are omnidirectional, some are directional. Also, the signal is not truly omnidirectional (like in a sphere around the antenna) but varies along the length and is also perpendicular. This gives a sort of doughnut shaped space around the antenna. If the antenna is vertical, the strongest signal will be found on the same level in a horizontal direction. The power of the antenna is given as a measurement such as 20 dBm (equivalent to 100 mW).
Typically, a wireless router rated as 802.11b or 802.11g will have a range of about 32m (120 ft) indoors and 95m (300 ft) outdoors. In theory, 802.11n routers can exceed that by more than two times. However, all these distances are affected by various factors. These not only include interference from adjacent networks but also other devices that operate n the 2.4 GHz band. These include baby alarms, cordless phones and microwave ovens. Also, physical obstacles such as buildings will affect the signal strength and quality. Some reports even claim that chicken wire in plaster walls can kill wi-fi signals almost completely. As this was a technique used by some Victorian builders, if you live in a Victorian house with walls like these then you are going to have problems.
Some manufacturers, such as hField technologies of the U.S., claim that their devices can provide better signal strength and signal quality through the use of proprietary technology. Certainly, their claims for their Wi-Fire adapter have been backed up in many a review over the years and so far no-one has sued them for the Wi-Fire not living up to the claims of range to 1,000 feet with signal strength being improved to 300% compared to internal wireless cards in laptops. [I must declare my own interest at this point. As the UK distributor of the Wi-Fire I am somewhat biased. I sell it because it lives up to its claims but you should read the reviews and make up your own mind before purchasing the Wi-Fire.]
Another aspect of the power requirements of wi-fi devices is that they are fairly high consumers of electricity and this means that always leaving your wireless card in your laptop on will deplete your battery quicker. The advice is to turn off your wireless card when not needing to connect to a network or browse the internet. Same principle applies to your smart-phone by the way, so if yours comes with wi-fi, turn it off when not needing to use it. This also applies to bluetooth but as this requires less power than wi-fi it will run your battery down less.
I mention Ethernet here as although wireless networks don’t rely on wires (hence the name), wireless routers come with with Ethernet ports and it’s not uncommon to first connect your computer via Ethernet cable to set up your router and especially when setting up security (see below) on it.
Ethernet is standardised as IEEE 802.3 (see above under IEEE). The combination of the twisted pair versions of Ethernet for connecting end systems to the network, along with the fiber optic versions for site backbones, is the most widespread wired LAN technology. It has been used from around 1980 to the present, largely replacing competing LAN standards such as token ring, FDDI, and ARCNET.
You should never operate your network without security. The risks have increased since the introduction of Wi-Fi and so its vital to make sure your network is secured. Unlike wired networks, wireless ones broadcast information widely in the vicinity of your devices (router and computer’s wireless card or adapter). This means its possible to someone, with the right knowledge and equipment, to snoop on your network traffic and using software, hack into your system, perhaps stealing passwords, personal information, downloading files from your computers and even using your internet connection to illegally download files or upload viruses etc. A German citizen was recently prosecuted for having an unsecured wireless network which someone else used to illegally download files from the internet so its important to secure your network.
Security begins with the router itself and once again you will need to login to the configuration page using a web browser (Firefox or Safari or Internet Explorer). Usually you type in an I.P. address in the format 192.168.x.x where it might be for example 192.168.1.1 or 192.168.2.1. Once the configuration page has loaded you will find a menu with various options, one of which will be labeled ‘Security’. There you will find various settings such as SSID and password.
Service set identifier, or SSID, is simply a name that identifies a particular 802.11 wireless LAN. It’s wise not to use something too obvious for your network name, such as ‘familyname’ or ‘name+house number’, e.g. ‘Robertsons‘ or ‘Smith72.’ Likewise, its best to change it from the default as these are widely known. I recommend something boring and meaningless to any would-be hacker such as ‘networkdefault‘or simply ‘default‘.
Passwords are easy to get wrong. Many people use ones that are too easy to crack such as ‘Frido68‘ or ‘heidismith22‘. Usually a minimum of 6 characters is required and it must consist of at least one letter and one number character. However, its best to include characters such as punctuation (! or ; or ? for example) and other symbols (such as @ or % or $) as well. Even better is to use a secure password generator such as 1Password or an extension for Firefox or Safari that will easily generate a secure password and will also store it securely for you. Such secure passwords will look something like 7vbZx4Z&*UZJeccPDF. Not easy to remember but even harder to crack, which is what matters. bear in mind you will need to write this down if you have other computers on the network in order to set them up to use your network but once this is done you should destroy the note.
So, that’s all for now. In another post I will cover some of the other annoying acronyms used when talking about networks such ‘ad-hoc‘ and ‘repeater‘.
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