Wi-Fi

Wi-Fi (or Wi-fi, WiFi, Wifi, wifi) is short for "Wireless Fidelity", a notion which is a set standard used for Wireless Local Networks (Wireless Local Area Networks - WLANs) based on IEEE 802.11 specification. The latest standards of specifications 802.11a or b, such as 802.16 g, is currently in preparation, the latest specification will offer many improvements ranging from more extensive coverage to the transfer speed. Wi-Fi originally intended for the use of wireless devices and the Local 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 by using an access point (or known as hotspots) nearby. Specification Wi-Fi was designed based on the IEEE 802.11 specification. Today there are four variations of 802.11, as follows: 802.11a, 802.11b, 802.11g, and 802.11n. Specifications b is the first Wi-Fi products. The variation of 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, n
In many parts of the world, the frequencies used by Wi-Fi, users are not required to obtain permission from local regulators (eg, Federal Communications Commission in the U.S.). 802.11a uses a higher frequency and therefore narrower jangkaunya power, 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 Operational Technically, Wi-Fi is one variant of communications and information technology that works on the network and device WLANs (wireless local area network). In other words, the Wi-Fi is the trade name (certification) provided to manufacturers of telecommunications equipment (Internet) working in WLANs and network interoperability already meet the required quality. Technology-based Wi-Fi Internet created and developed a group of U.S. engineers who worked at the Institute of Electrical and Electronis Engineers (IEEE) technical standards-based numbered devices 802.11b, 802.11a and 802.16. Wi-Fi devices are not only able to work on WLAN networks, but also on network Wireless Metropolitan Area Network (WMAN). Because the device with the technical standard 802.11b WLAN devices intended for use in the 2.4 GHz frequency or frequencies, commonly called ISM (Industrial, Scientific and Medical). As for the technical standards 802.11a and 802.16 WMAN or destined for the device is also called Wi-Max, who works in the vicinity of 5 GHz frequency band. High public interest - particularly among the Internet community - using Wi-Fi technology because at least two factors. First, the ease of access. This means that users in one area can access the Internet simultaneously without having to be bothered with cables. Consequently, users who want to do surfing or browsing news and information on the Internet, simply bring the PDA (pocket digital assistance) or Wi-Fi enabled laptop into a place where there is access point or hotspot. The proliferation of hotspots in places such - which was built by the telecom operators, Internet service providers and even individual people - triggered the second factor, namely because construction costs are relatively cheap or only around 300 dollars U.S.. Increasing the quantity of Internet users based Wi-Fi technology is increasingly implicated in various parts of the world, has encouraged Internet service providers (ISPs) to build hotspots in major cities of the world. Some observers have even predicted in 2006, there will be 800,000 hotspots in the countries of Europe, 530,000 in the United States and one million in countries in Asia. The overall amount of income derived by the United States and European countries of technology-based Internet business Wi-Fi until the end of 2003 was estimated at 5.4 trillion U.S. dollars, an increase of 33 billion U.S. dollars from the year 2002 (www.analysys.com). Plague In Indonesia alone, the use of Internet-based Wi-Fi already implicated in several major cities. In Jakarta, for example, the maniacs who are surfing the Internet while waiting for the plane took off at the airport waiting room, was not an alien. The same phenomenon seen in many cafes - like Starbuck's Café and La Moda Cafe in Plaza Indonesia, the Coffee Club Senayan, and Mister Bean Coffee Cafe at Cilandak Town Square - where the visitor can open the Internet to look at political news or the latest gossip while sipping a cappuccino artist heat. Today, business telephone-based VoIP (Voice over Internet Protocol) has also been using Wi-Fi technology, where calls are forwarded through the WLAN network. The application is named VoWi-FI (Voice over Wi-Fi). Some time ago, the latest technical standards created by the IEEE has been able to support the operation of a streaming video service. Even the predictable, the future can be made cards (card)-based Wi-Fi technology that can be inserted into electronic equipment, ranging from digital cameras to video game consoles (ITU News 8 / 2003). Based on the above explanation, it can be concluded that the quantity of business and technology, Wi-Fi users tend to increase, and economically it has a positive impact on the national economy of a country, including Indonesia. Nevertheless, the government should address the phenomenon wisely and carefully. The reason is, technologically frequency bands - both 2.4 GHz and 5 GHz - which became operational container technology, Wi-Fi is not free of limitations (Kompas, 2/5/2004). Because the users in a new area can take advantage of wireless Internet system is optimally, when all the devices used in the area using a uniform transmit power and limited. If the preconditions are not honored, you can bet will happen is not only harmful interference between devices of Internet users, but also with other telecommunications systems devices. If interference continues - because users want more superior than other users, and therefore lack of understanding of the limitations of the technology - in the end will make the path a frequency of 2.4 GHz and 5 GHz could not be used optimally. Another limitation of this second wireless frequency bands (particularly 2.4 GHz) is due also used for ISM (industrial, science and medical). Consequently, the use of radio communications or other telecommunication device that works in the frequency band it should be ready to accept interference from ISM devices, as stated in S5.150 of the Radio Regulations. In the recommendation ITU-R SM.1056, also informed the device characteristics of the ISM which basically aims to prevent occurrence of interference, both between devices with the ISM as well as telecommunications equipment sharing. The same recommendation affirms that every member of the ITU-free establish administrative requirements and rules of law relating to mandatory power restrictions. Recognizing the limitations and the impact that may arise from the use of both of the wireless frequency bands, various countries and impose regulations that limit the transmission power of the devices used. More to know about Wi-Fi Wi-Fi (Wireless Fidelity) is a wireless connection such as mobile phones using radio technology so that users can transfer data quickly and securely. Wi-Fi not only allows you to access the Internet, Wi-Fi can also be used to create wireless networks in the enterprise. Because of that many people associate with Wi-Fi "Freedom" because Wi-Fi technology gives freedom to users to access the Internet or transferring data from the meeting room, hotel rooms, campus, and cafes are marked "Wi-Fi Hot Spot." Also one of the advantages of Wi-Fi is a speed several times faster than the fastest cable modem. So Wi-Fi users no longer have to be in office space to work. But Wi-Fi can only be accessed by computer, laptop, PDA or Cellphone that has been configured with Wi-Fi certified radio. For laptops, the user can install a Wi-Fi PC Cards in PCMCIA card-shaped slot that has been available. For PDA, the user can install the Compact Flash format Wi-Fi radio in the slots you have available. For users who are computer or PDA - it uses Windows XP, simply by putting the card into an available slot, Windows XP will automatically detect the area around you and look for Wi-Fi network that is closest to you. It is very easy to find signs of whether the device has a Wi-Fi facility, that is by looking at Wi-Fi CERTIFIED logo on the packaging. Although Wi-Fi can be accessed only place marked with "Wi-Fi hotspot", the number of public places that offer "Wi Fi Hotspot" increased dramatically. This is due to maketh their place as "Wi-Fi Hotspot" means their customers can access the Internet, which means giving added value to our customers. Wi-Fi service offered by each of the "Hots Spot" also varied, some offering free access as well as in airport executive lounges, some require users to become subscribers of an ISP that offers free Wi-Fi and there is also a offer pre-paid card. Whatever your choice for how to access Wi-Fi, the most important is the presence of Wi-Fi, you can work anywhere and at anytime until you do not need to be always locked in your workspace to complete each task.


Wireless Technology
Pioneered the development of wireless Internet access in Bogor, PT Bonet Utama provide its Internet connection via VSAT (Very Small Apateur Terminal) to the World Wide Web. This is to provide options for users of the Internet to send emails and download data that does not depend on dial-up telecommunications infrastructure. Wireless computer networking technology to access the Internet may be regarded as starting from ITB campus in Bandung, which at that time led by Dr. Onno W. Purbo CNRG with his team, where they assemble a simple PC computer equipped with an additional FreeBSD WaveLAN PCMCIA cards and ethernet cards, assisted with an outdoor antenna so it can reach far enough distance connections.
Subterfuge which is the result of pure creativity is to this day still used by many cafes and medium enterprises, although the name WaveLAN PCMCIA card that was already deceased, his company was bought by Lucent, for then changed the name of its product into the Orinoco from Avaya, its subsidiary Lucent. So, are encouraged to not mention the wireless technology known as WaveLAN, because of its connotation is wrong and can laugh at people who study this technology, simply called WLAN or Wireless-LAN. The technology used by his group CNRG at that time actually using one of the IEEE standard, which is a collection of engineers from around the world (rather than American), which spawned the 802.11 standard that is standard with network communication without using a cable and use the 2.4 GHz frequency. At that time, experiments conducted using WaveLAN cards can only move data at 2Mbps, being present, the standard that is widely used is 802.11b that can move data up to 11Mbps, and next year will likely be replaced or shifted to the 802.11g standard that can be move data up to 50Mbps!.
Use 802.11 or 802.11b standard, designed for use indoors (indoor) is actually very inefficient and can mutually interfere with each other, as most 802.11 systems are always looking for his colleagues who are also 'on water', thus slowing the performance of access what we want. Imposition of this technology is based on cheap and affordable price factor, because the standard 802.11 and 802.11b is the common standard for communication in the room, so many companies in Taiwan that make it, make it affordable, around USD 75 to USD 125 per unit basis.
Problems that often occur in the field, namely the pemasangnya limited knowledge, so that the device is really only used indoors, and if enforced could only work at a distance of about 6 km of this, forced again to be able to communicate up to tens of kilometers with the help of the amplifier. This causes kisruhnya use 2.4 GHz which is in the United States is a frequency that is free to use without needing to register or notify the authorities.

To use 2.4 GHz in the outdoors, we must use the device that follow the 802.16 standard, namely IEEE standard for Wireless MAN (Metropolitan Area Network), so it is not imposing 802.11 and 802.11b.

This problem is actually very dependent on the budget and the purchasing power of the user community, where economic crisis and stagnation in the business world, leading IT players really have to tighten the belt plate, using a device that seirit-efficient as possible.
Unfortunately, the 802.16 standard, has not been 'cooked', so not many companies that follow these standards, and most importantly, its economic scale is still high and the price is certainly still beyond the company's lower-middle.
2.4 GHz technology development is very fast at all, let alone supported by the industry in Taiwan who are ready to make this product as a mass product with a selling price that every day more and more cheap and more powerful.
In the early 2000s ago, there are several Taiwanese and Japanese companies that make a breakthrough, namely by making what is often referred to as Wireless in The Box, which is the 'creation' Onno and his friends are packed in a smaller form , without using a computer.
Wireless In The Box (WITB) contains a PCMCIA card installed in an electronic board that is designed in such a way that can move data from the radio is on a PCMCIA to ethernet channel. So, there are two connections on the WITB, a connection to an external antenna, a connection standard RJ-45 Ethernet, and two other standard serial connection for initial setup, and power connections to the 9 volt adapter. WITB connected to a switch or hub in a local network, and then by using the software that comes on these units, we can set various parameters, such as setting the IP address, the client and access point, and other settings is the completeness of the use WITB. The technology used by his group CNRG at that time actually using one of the IEEE standard, which is a collection of engineers from around the world (rather than American), which spawned the 802.11 standard that is standard with network communication without using a cable and use the 2.4 GHz frequency. At that time, experiments conducted using WaveLAN cards can only move data at 2Mbps, being present, the standard that is widely used is 802.11b that can move data up to 11Mbps, and next year will likely be replaced or shifted to the 802.11g standard that can be move data up to 50Mbps!.
Use 802.11 or 802.11b standard, designed for use indoors (indoor) is actually very inefficient and can mutually interfere with each other, as most 802.11 systems are always looking for his colleagues who are also 'on water', thus slowing the performance of access what we want. Imposition of this technology is based on cheap and affordable price factor, because the standard 802.11 and 802.11b is the common standard for communication in the room, so many companies in Taiwan that make it, make it affordable, around USD 75 to USD 125 per unit basis.

Problems that often occur in the field, namely the pemasangnya limited knowledge, so that the device is really only used indoors, and if enforced could only work at a distance of about 6 km of this, forced again to be able to communicate up to tens of kilometers with the help of the amplifier. This causes kisruhnya use 2.4 GHz which is in the United States is a frequency that is free to use without needing to register or notify the authorities.
To use 2.4 GHz in the outdoors, we must use the device that follow the 802.16 standard, namely IEEE standard for Wireless MAN (Metropolitan Area Network), so it is not imposing 802.11 and 802.11b.
This problem is actually very dependent on the budget and the purchasing power of the user community, where economic crisis and stagnation in the business world, leading IT players really have to tighten the belt plate, using a device that seirit-efficient as possible.
Unfortunately, the 802.16 standard, has not been 'cooked', so not many companies that follow these standards, and most importantly, its economic scale is still high and the price is certainly still beyond the company's lower-middle.
2.4 GHz technology development is very fast at all, let alone supported by the industry in Taiwan who are ready to make this product as a mass product with a selling price that every day more and more cheap and more powerful.
In the early 2000s ago, there are several Taiwanese and Japanese companies that make a breakthrough, namely by making what is often referred to as Wireless in The Box, which is the 'creation' Onno and his friends are packed in a smaller form , without using a computer.
Wireless In The Box (WITB) contains a PCMCIA card installed in an electronic board that is designed in such a way that can move data from the radio is on a PCMCIA to ethernet channel. So, there are two connections on the WITB, a connection to an external antenna, a connection standard RJ-45 Ethernet, and two other standard serial connection for initial setup, and power connections to the 9 volt adapter. WITB connected to a switch or hub in a local network, and then by using the software that comes on these units, we can set various parameters, such as setting the IP address, the client and access point, and other settings is the completeness of the use WITB. If it takes a long distance to connect two points, preferably using a device that is specifically for long distance and use the 2.4 GHz frequency instead.


Noise and interference
Noise that occurs, is caused by other devices that work at around 2.4 GHz, such as micro-wave oven, blue tooth devices, and others, because we know that the frequency of 2.4 GHz was originally used for industrial, scientific, and medical ( ISM band).
Interference caused by other 2.4GHz device users, who worked on the same line.
Regulations that will apply
Until now, the government through Postel has not made definite rules about the frequency of 2.4 GHz frequency which in America is free for use by various circles. The formulation of this rule is still thrown-throwing between the post and telecommunications and wireless user community, often called IndoWLI and gather all the mailing lists IndoWLI@yahoogroups.com
In the near future there will be rules that require wireless device users to pay taxes or registration fee based on the number of its base station.
All the constraints and issues surrounding the use and utilization of warm This wireless technology is still a problem that cross each other and there are some that can not be solved quickly, even if the users or potential users, is hoping very big on this technology.