Closer Understanding What Is Wifi?

Wi-Fi (or Wi-fi, WiFi, Wifi, wifi) is short for Wireless Fidelity, has a standard set of terms that is used for Wireless Local Networks (Wireless Local Area Networks - WLANs) based on IEEE 802.11 specification. Latest standard specifications 802.11a or b, such as 802.16 g, is currently in preparation, the new specification offers many improvements ranging from broad coverage to further transfer speed.

Wi-Fi originally intended for use of wireless devices and Local Area Network (LAN), but now more widely used to access the Internet. These enable anyone with a computer with a wireless card (wireless card) or personal digital assistant (PDA) to connect to the internet using access point (or known as hotspots) nearby.


Specifications

Wi-Fi was designed based on the IEEE 802.11 specification. Today there are four variations of 802.11, namely: 802.11a, 802.11b, 802.11g, and 802.11n. Specification b is the first product of Wi-Fi. Variation g and n is one product that has the most sales in 2005.
Specifications Wi-Fi
Specifications Speed Frequency
Band Match
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



In many parts of the world, the frequencies used by Wi-Fi, users are not required to obtain permission from local regulators (eg, the Federal Communications Commission in the U.S.). 802.11a uses a higher frequency and therefore a narrower coverage, others the same.

Wi-Fi version of the most extensive in the U.S. market today (based in IEEE 802.11b / g) operates at 2400 MHz to 2483.50 MHz. With so allows operation in 11 channels (each 5 MHz), centered on the following frequencies:

* Channel 1 to 2.412 MHz;
* Channel 2 to 2.417 MHz;
* Channel 3 to 2.422 MHz;
* Channel 4 to 2.427 MHz;
* Channel 5 to 2.432 MHz;
* Channel 6 to 2.437 MHz;
* Channel 7 to 2.442 MHz;
* Channel 8 to 2.447 MHz;
* Channel 9 to 2.452 MHz;
* Channel 10 to 2.457 MHz;
* Channel 11 to 2.462 MHz