Wi-Fi is designed based on the IEEE 802.11 specification. Currently there are four variations of 802.11, namely: 802.11a, 802.11b, 802.11g and 802.11n. B product specification is the first Wi-Fi. Variations g and n is one product that has the most sales in 2005.
Specifications Speed Frequency Band Matches with 802.11b 11 Mb / s 2.4 GHz b 802.11a 54 Mb / s 5 GHz a 802.11g 54 Mb / s 2.4 GHz b, g 802.11n 100 Mb / s 2.4 GHz b, g, n
In many parts of the world, the frequency used by Wi-Fi, users are not required to obtain permission from the local regulator (eg, the Federal Communications Commission in the U.S.). 802.11a uses a higher frequency and therefore power range more narrow, the other the same.
Wi-Fi version of the most extensive in the U.S. market now (based on the IEEE 802.11b / g) operates at 2400 MHz to 2483.50 MHz. With so allow operation in 11 channels (each 5 MHz), centered in the frequency of the following:
* Channel 1 - 2.412 MHz;
* Channel 2 - 2.417 MHz;
* Channel 3 - 2.422 MHz;
* Channel 4 - 2.427 MHz;
* Channel 5 - 2.432 MHz;
* Channel 6 - 2.437 MHz;
* Channel 7 - 2.442 MHz;
* Channel 8 - 2.447 MHz;
* Channel 9 - 2.452 MHz;
* Channel 10 - 2.457 MHz;
* Channel 11 - 2.462 MHz
Technically, operational, Wi-Fi is one of the variants of information and communications technology that works on the network devices and WLANs (wireless local area network). In other words, Wi-Fi is the trade name (certification), which is given to the device manufacturer of telecommunications (Internet) that work in the network and WLANs already meet the required quality of interoperability.
Internet technology-based Wi-Fi is created and developed by a group of engineers of the United States who are working in the Institute of Electrical and Electronis Engineers (IEEE) technical device based on the standard numbered 802.11b, 802.11a and 802.16. Wi-Fi device is not only able to work in the WLAN network, but also in the network Wireless Metropolitan Area Network (WMAN).
Because the device is 802.11b technical standard for WLAN devices used in the 2.4 GHz frequency or frequencies that are commonly called ISM (Industrial, Scientific and Medical). For devices that are standard technical 802.11a and 802.16 allocated for the device or WMAN also called Wi-Max, who works at the tape around 5 GHz frequency.
The high-energy community, especially among the community-use Internet technology, Wi-Fi because at least two factors. First, the ease of access. This means, users in one area can access the Internet without the need to simultaneously according cable.
Consequently, users who want to do surf or browsing news and information on the Internet, simply take a PDA (pocket digital assistance) or laptop Wi-Fi leaders to places where there is access point or Hotspot.
There are more Hotspot in places such built by telecommunications operators, Internet service providers and even individuals, triggered the second factor, namely, because the cost of building a relatively cheap, or only around 300 dollars the United States.
Increasing the quantity of Internet users based Wi-Fi technology that is increasingly phenomenon in various parts of the world, has encouraged Internet service providers (ISPs) to build a hotspot in the big-city world.
Some observers even predict the year 2006, there will be as many as 800,000 Hotspot in the countries of Europe, 530,000 in the United States and one million in Asian countries.
The overall amount of revenue earned the United States and European countries from the business Internet-based technology, Wi-Fi until the end of the year 2003 is estimated a total of 5.4 trilliun U.S. dollars, or an increase of 33 billion U.S. dollars from 2002