Definition and history of Wi-Fi (Wireless Fidelity)

Kaitkata: acess point, band, cafe, frequency, hot spots, Hz, Internet, computer, laptop, Know, pc, specifications, wiring tanpoa, Transfers, Wifi, Wireless 0
Wi-Fi is short for Wireless Fidelity, which has a standard set of terms that are used for Wireless Local Networks (Wireless Local Area Networks - WLAN) based on the IEEE 802.11 specification. The latest standard of 802.11a or b specifications, such as 802.11 g, is currently in preparation, the latest specification will offer much improved from a more extensive coverage far as transfer speed. Wi-Fi not only be used for internet access, Wi-Fi can also be used to create wireless networks in the enterprise. Because of that many people associate with the Wi-Fi œKebebasanâ â € €? because the Wi-Fi technology gives the freedom to the users to access the internet or transfer data from the meeting room, hotel rooms, college campuses, and cafà ©-marked Cafà © â € œWi-Fi Hot Spotâ €?. Originally Wi-Fi is intended for use wireless devices, and Local Area Network (LAN), but now more widely used to access the Internet. This allows anyone with a computer with a wireless card (wireless card) or personal digital assistant (PDA) to connect to the internet using access point (or hotspot known) nearby.

Specification

Wi-Fi is designed based on the IEEE 802.11 specification. Today there are four variations of the 802.11, namely: 802.11a, 802.11b, 802.11g, and 802.11n. Specifications b is the first Wi-Fi product. Variations g and n is one product that has the most sales in 2005.
Specifications Wi-Fi
Specifications Frequency Speed
Suitable Band
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
Technically operational, Wi-Fi is one of the variants of communication and information technology that works on the network and device WLAN (wireless local area network). In other words, Wi-Fi is a trademark certification granted to telecommunications equipment manufacturers (internet) working in a WLAN network and interoperates capacity meets the required quality.
Internet technology-based Wi-Fi is built and developed a group of engineers who worked on the United States Institute of Electrical and Electronis Engineers (IEEE) technical standard based devices numbered 802.11b, 802.11a and 802.16. Wi-Fi device is not only able to work on WLAN networks, but also in tissue Wireless Metropolitan Area Network (WMAN).
Due to the technical standard 802.11b WLAN devices intended for use in the 2.4 GHz frequency or commonly known as ISM (Industrial, Scientific and edical). Moderate technical standards for devices intended for 802.11a and 802.16 WMAN devices or also called Wi-Max, which works around the 5 GHz frequency band.

Excess Wi-fi

The high interest of people-especially among the Internet community-use Wi-Fi technology because at least two factors.
1) ease of access. This means that users in one area can access the Internet simultaneously without having to bother with cables.
2) users who want to surf or browse news and information on the Internet, simply bring the PDA (pocket digital assistance) or Wi-Fi enabled laptop to a place where there is an access point or hotspot.
The proliferation of hotspots in such places, built by telecommunication carriers, Internet service providers and even individuals-triggered second factor, which is due to the relatively low construction costs or only around 300 dollars U.S.. Also one of the advantages of Wi-Fi is the speed is several times faster than the fastest cable modem. So Wi-Fi users no longer have to be in the office to work

Wi-Fi Hardware

Hardware wi-fi available in the market today there be
Wi-fi in the form of PCI Wi-fi in the form of USB
There are 2 modes of access to Wi-Fi, which is
Ad-Hoc
This connection mode is the mode where multiple computers are connected directly, or better known as Peer-to-Peer. The advantage, cheaper and more practical when connected only 2 or 3 computers, without having to buy an access point
Infrastructure
Using the Access Point that serves as a regulator of the data traffic, allowing many Client can be connected through a network (Network).

Weakness on wifi

Easily dihacking by hackers to steal user passwords wi-fi
How are the following:
First we must know the difference between the Hub and Switch:
* On a network hub all data flowing on the network can be viewed / picked up by any computer on the network computer asalakan requesting the data, if not requested ya will not come.
* In the computer network switches only exchange data to see the data, others are not entitled komputer2 requesting data.
The problem is the price of routers hubs and switches do not vary much so most places are now using the switch that makes it difficult for network hacking.