- Connecting people
Technology is making rapid progress and is making many things easier.As the innovative thinking of persons is increasing day-by-day,new methods for wireless networking has been evolved of which our present topic Wi-Fi is the most accepted technology.
Wi-Fi, an acronym for Wireless-Fidelity which is the wireless way to handle networking.The main aim of this paper is wireless networking achieved by Wi-Fi.This paper introduces Wi-Fi technology and states the history of this technology in brief.We then deal with the different ways of wireless networking,connecting wi-fi and with wi-fi security.This paper concludes with the pros and cons of this technology and it’s future.
Wi-Fi, an acronym for "Wireless Fidelity", is a set of product compatibility standards for Wireless Local Area Networks (WLAN) based on the IEEE 802.11 specifications. Wi-Fi was intended to be used for mobile devices and LANs, but is now often used for Internet access. It enables a person with a wireless-enabled computer or personal digital assistant (PDA) to connect to the Internet when in proximity of an access point.
Wireless Fidelity is the wireless way to handle networking. It is also known as 802.11 networking and wireless networking. Using this technology we can connect computers anywhere in a home or office without the need of any wires. The computers connect to the network using radio signals, and they can be up to 100 feet or so apart.
Wi-Fi allows to connect to the internet from virtually anywhere at speeds of up to 54Mbps.The computers and handsets enabled with this technology use radio technologies based on the IEEE 802.11 standard to send and receive data anywhere within the range of a base station.
Wi-Fi goes beyond wirelessly connecting computers, it also connects people.
· IEEE (Institute of Electrical and Electronics Engineers) established the 802.11 group in 1990.
· Initial speeds were 1 and 2 Mbps.
· IEEE modified the standard in 1999 to include 802.11a and b.
· 802.11g was added in 2003.
· 802.11 equipment first available, then a, followed by g.
4.1.Wi-Fi’s Walkie-Talkie Network:
To understand the wire less technology let us consider a pair of Walkie-Talkies.These are small radios that can transmit and receive radio signals.When we talk into a Walkie-Talkie, our voice is picked up by a microphone, encoded onto a radio frequency and transmitted with the antenna. Another Walkie-Talkie can receive the transmission with its antenna, decode our voice from the radio signal and drive a speaker.Simple Walkie-Talkies like this transmit at a signal strength of about 0.25 watts, and they can transmit about 500 to 1,000 feet.If we want to connect two computers together in a network using Walkie-Talkie technology:
- Equip each computer with a Walkie-Talkie.
- Give each computer a way to set whether it wants to transmit or receive.
- Give the computer a way to turn its binary 1s and 0s into two different beeps that the walkie-talkie could transmit and receive and convert back and forth between beeps and 1s/0s.
This would actually work. The only problem would be that the data rate would be very slow. Walkie-talkie is designed to handle the human voice.So it is not being able to send very much data in this way(may be 1,000 bits per second).
Any products tested and approved as "WiFi Certified" by the WiFi Alliance are certified as interoperable with each other, even if they are from different manufacturers. A user with a "Wi-Fi Certified" product can use any brand of access point with any other brand of client hardware that also is certified. Typically, however, any Wi-Fi product using the same radio frequency (for example, 2.4GHz for 802.11b or 11g, 5GHz for 802.11a) will work with any other, even if not "Wi-Fi Certified."
4.2.Wi-Fi's Radio Technology:
The radios used in Wi-Fi are not so different from the radios used in walkie-talkies. There are three big differences between Wi-Fi radios and Walkie-talkies.
- WiFi radios that work with the 802.11b and 802.11g standards transmit at 2.4 GHz, while those that comply with the 802.11a standard transmit at 5 GHz. Normal walkie-talkies normally operate at 49 MHz. The higher frequency allows higher data rates.
- WiFi radios use much more efficient coding techniques that also contribute to the much higher data rates. For 802.11a and 802.11g, the technique is known as orthogonal frequency-division multiplexing (OFDM). For 802.11b, it is called Complementary Code Keying (CCK).
- The radios used for WiFi have the ability to change frequencies. 802.11b cards can transmit directly on any of three bands, or they can split the available radio bandwidth into dozens of channels and frequency hop rapidly between them. The advantage of frequency hopping is that it is much more immune to interference and can allow dozens of WiFi cards to talk simultaneously without interfering with each other.
5.1.Adding WiFi to a Computer:
Many new laptops come with a Wi-Fi card built in. It is also easy to add a Wi-Fi card to an older laptop or a desktop PC. The process is
- Take a 802.11a, 802.11b or 802.11g network card. 802.11g has the advantage of higher speeds and good interoperability on 802.11b equipment.
- For a laptop, this card will normally be a PCMCIA card that slide into a PCMCIA slot on laptop. Or take a small external adapter and plug it into a USB port.
- For a desktop machine, take a PCI card & install inside the machine, or a small external adapter and connect to the computer with a USB cable.
- Install the card
- Install the drivers for the card
- Find an 802.11 hotspot
- Access the hotspot.
A hotspot is a connection point for a Wi-Fi network.
It is a small box that is hardwired into the Internet. The box contains an 802.11 radio that can simultaneously talk to up to 100 or so 802.11 cards. There are many Wi-Fi hotspots now available in public places like restaurants, hotels, libraries and airports. We can create our own hotspot in our home.
On the newest machines, an 802.11 card will automatically connect with an 802.11 hotspot and a network connection will be established. As soon as we turn on our machine, it will connect and we will be able to browse the web, send email, etc using Wi-Fi. On older machines we often have to go through this simple 3-step process to connect to a hotspot:
- Access the software for the 802.11 card- normally there is an icon for the card down in the system tray at the bottom right of the screen.
- Click the "Search button" in the software. The card will search for all of the available hotspots in the area and shows a list.
- Double-click on one of the hotspots to connect to it.
- On ancient 802.11 equipment, there is no automatic search feature. We have to find what is known as the SSID (server set id) of the hotspot (usually a short word of 10 characters or less) as well as the channel number (an integer between 1 and 11) and type these two pieces of information in manually. All the search feature is doing is grabbing these two pieces of information from the radio signals generated by the hotspot and displaying them for us.
· Data Security /Encryption
§ Third Party solution-Fortress
§ Wi-FI protected Access(WPA)
§ Wired Equivalent privacy (WEP)-shared key.
§ Close system-No advertising
§ Mac Authentication –Mac address control
· Attack-Denial of service
· Client protection
Wi-Fi hotspots can be open or secure. If a hotspot is open, then anyone with a Wi-Fi card can access the hotspot. If it is secure, then the user needs to know a WEP key to connect.
7.Hotspot in Home:
7.1.Setting up a Hotspot in a Home:
It is very easy to set up a Wi-Fi hotspot in home. It can be done in one of the two ways:
- If there are several computers hooked together on an Ethernet network and want to add a wireless hotspot to the mix, purchase a Wireless Access Point and plug it into the Ethernet network.
- If it is the first time to set up a network in home, or to upgrading, buy a Wireless Access Point Router. This is a single box that contains: 1) a port to connect to cable modem or DSL modem, 2) a router, 3) an Ethernet hub, 4) a firewall and 5) a wireless access point. Connect the computers to this box either with traditional Ethernet cables or with wireless cards.
Either way, once turn our Wireless Access Point on, there is a Wi-Fi hotspot in house. In a typical home, the new hotspot will provide coverage for about 100 feet (30.5 meters) in all directions, although walls and floors do cut down on the range. Even so, we get good coverage throughout a typical home. For a large home, buy inexpensive signal boosters to increase the range of the Hotspot.
7.2.Configuring a New Hotspot in Home:
Searching for hotspot
Most wireless access points come with default values built-in. Once we plug them in, they start working with these default values in 90 percent of the cases. However, we may want to change things. You normally get to set three things on the access point:
- The SSID -- it will normally default to the manufacturer's name. We can set it to any word or phrase.
- The channel -- normally it will default to channel 6. However, if a nearby neighbor is also using an access point and it is set to channel 6, there can be interference. Choose any other channel between 1 and 11. An easy way to see if our neighbors have access points is to use the search feature that comes with your wireless card.
- The WEP key -- The default is to disable WEP. To turn it on, enter a WEP key and turn on 128-bit encryption.
Access points come with simple instructions for changing these three values. Normally do it with a Web browser. Once it is configured properly, we can use our new hotspot to access the Internet from anywhere in our home.
8.Advantages of Wi-Fi:
1. Wi-Fi is a core technology in GPS Industries Applications.
2. Wi-Fi technology available in hotels, airports, etc., will be more inclined to bring laptop with us when traveling for personal reasons.
3. Frees network devices from cables, allows for a more dynamic network to be grown.
Changes the way people live, communicate, work and play.
4. Many reliable and bug-free Wi-Fi products on the market
5.It helps to become more productive at home, like online shopping and banking;
6. Wi-Fi technology allows getting out of home office and working in other rooms.
8.Disadvantages of Wi-Fi:
1.The 802.11b and 802.11g flavors of Wi-Fi use the 2.4 GHz spectrum, which is crowded with other devices such as Bluetooth, microwave ovens, cordless phones, or video sender devices, among many others.
2.Power consumption is fairly high compared to other standards, making battery life and heat a concern.
3.It is not always configured properly by users.
There will be a requirement for technologies such as WLAN in this application. In the cellular terminal market there is room to accommodate numerous wireless technologies and a feature set incorporating WLAN looks likely to be adopted in around 25% of terminals by 2009.For the WLAN market, the notebook/laptop is proving to be one of the most important growth areas for the technology. IMS Research has predicted WLAN penetration into notebooks will be in excess of 90% by 2007.Generate more revenue as wireless internet access attracting more business customers, corporate events and outlines.
As Wi-Fi is now shipped in millions of products and deployed in millions of homes, business and hotspots worldwide, the technology has moved beyond the realm of a computer feature. Wi-Fi has fast become a cultural phenomenon.