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Our Expertise:
Wi-Fi is one of the most common buzzwords used at the moment, and it's earned this status
due to its massive flexibility and power. Put simply, Wi-Fi is a wireless way of networking computers. It is also
commonly referred to as 802.11 networking or wireless networking. It allows you to connect your computers to the
network using radio signals, and has a maximum radius of approximately 100 feet. The radios used in Wi-Fi allow
the computer to transmit and receive data by converting binary code into radio data and radio data into binary code.
Binary code is the series of 0's and 1's which make up digital data. Some features of Wi-Fi are:
- There are two main standards Wi-Fi works with: 802.11b and 802.11a. The former is the most common found as it
is relatively expensive, and allows the radio to transmit at frequencies of up to 2.4GHz. 802.11a is not so common
but supports frequencies of up to 5GHz, and subsequently allows for higher data transfer rates.
- Wi-Fi uses very efficient coding techniques that also allow for these very high data transfer rates. The coding
technique for the 802.11a standard is known as Orthogonal Frequency-Divison Multiplexing (OFDM). In the case of the
802.11b standard, the standard is called Complementary Code Keying (CCK).
- A great advantage of Wi-Fi is that its radios have the ability to change frequencies. Cards which comply with
802.11b can transmit directly on any of three bands, or they can split the available radio bandwidth into dozens of
channels and frequency hop quickly between them. Frequency hopping is a key element of Wi-Fi as it prevents interference
and allows many Wi-Fi cards to talk simultaneously without interfering with each other.
- Due to these high frequencies and encoding techniques, Wi-Fi radios have the ability to process a great amount of data
per second. 802.11b can handle up to 11 megabits per second (usually 7 megabits per second), but may fall back to 1 or
2 megabits per second if there is too much interference. 802.11a cards can handle up to 54 megabits per second (usually
around 30 megabits per second).
- All radios are installed directly on the card and are therefore invisible, making Wi-Fi an extremely attractive
technology. Add to this the extreme simplicity of using Wi-Fi, and you have a technology far superior to normal networking
conventions using CAT5 cables.
Installing Wi-Fi on your own computer is extremely simple. Most new notebook machines come with built-in Wi-Fi cards,
but you can also purchase PCMCIA cards for notebooks (or PCI cards for desktops) which will allow you to use Wi-Fi.
These cards are relatively inexpensive and installing them is a piece of cake. If you are using a notebook it is a
matter of simply inserting the PCMCIA card into the PCMCIA card slot and installing the drivers. In the case of
desktops, you may require a little bit of experience with installing cards, but the instructions with the card should
provide everything you need to get started.
The next thing you need to do is find a 802.11 hotspot. This is a small box which allows your computer to connect to
the Wi-Fi network. This box contains an 802.11 radio which is capable of talking to up to 100 802.11 cards
simultaneously. These hotspots are often located in hotels, restaurants, café's, libraries and airports. You can
also configure a 802.11 hotspot in your own home or office, which we will describe next.
Setting up your own hotspot is extremely simple. If you are in an office or you already have a network installed in your
home, it is as simple as purchasing a Wireless Access Point and plugging it into the Ethernet network. If you do not already
have a network installed you must buy a Wireless Access Point Router. This is a small box (about the size of an external
modem) which contains a port to connect to an ADSL/Cable modem; a router; an Ethernet hub; a firewall; and a Wireless
Access Point. You can now connect your computers to this box either using Wi-Fi cards or using traditional Ethernet cabling.
(This is a great advantage as it means the network is backward compatible with wired networks, meaning that if a computer
is out of range you can always use CAT5 cables to connect this computer to the network, and still use Wi-Fi cards on other
computers.
Once you have installed your hotspot, you can now connect computers with Wi-Fi cards to the network within a range of
about 100 feet. (Please note that this range is cut significantly by the presence of walls and floors). If you live
in a large home or work in a large office, cheap signal boosters can be purchased to increase this range.
Most Wireless Access Points come with default networking values built-in. These values almost always let you connect
to the network immediately using your Wi-Fi enabled computers. However, it is advisable to set your own settings, which
come in handy if anything goes wrong as you know exactly what values you have used. The following things may be set:
- The SSID, which is usually automatically configured to the manufacturers name (in the products we sell, it is
usually Netopia). This SSID can be changed to any word or phrase you want.
- The channel, usually set to 6 by default should be changed as if offices or houses nearby have Wireless Access
Points installed, they will nearly always be set to channel 6, leading to interference. You can find out if they are
using a channel by using the search feature which comes with the card. We recommend that you still choose any channel
between 1-11 (excluding 6) as you may encounter problems if people nearby install Wi-Fi at a later stage.
- The WEP (Wired Equivalent Privacy) Key, which is disabled by default. Enabling WEP requires you to enter a WEP
key and to turn on 128-bit encryption.
These values are simple to change, and depending on the manufacturer of your device, the values are usually changed
using your web browser (our Netopia products all use the web browser to change values). The product's instruction
manual should show you how to change these values.
Above we told you that you have an option to turn on a WEP key (Wired Equivalent Privacy). Having WEP disabled is
not recommended, as it means anyone can connect to your wireless network, without knowing the WEP key. This is
referred to as an "Open Hotspot". If it is secure, then the user needs to know the WEP key to connect to the system.
WEP is an encryption system for the data transmitted by 802.11. It is available in either 64-bit or 128-bit formats.
64-bit is actually 40-bit, and 128-bit is really 104-bit, reasons why they are known as 64-bit and 128-bit are
irrelevant to this web page. 40-bit encryption is known for being insecure and unstable, so it is advised to use
the secure 128-bit encryption system.
Wi-Fi is an excellent technology that is simple to install, simple to use, secure and stable. It allows fast data
transfers over a wide enough range and is a system which is useful for every home and office.
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