Wireless network journey: From Wi-Fi to WiMax

Wireless networking is one of the biggest advances in the computer industry. Last year, tens of millions of Wi-Fi devices were consumed and it is expected that this year there will be about 100 million users. The development path of this technology from a narrow scale to a large scale has only really begun 5 years ago.

The beginning

In 1985, the US Federal Communications Commission (the country's telecommunications regulator), decided to 'open up' some of the wireless bands, allowing them to be used without a license. goverment. This is quite an unusual thing at the time. But, in the conviction of technical experts, the FCC has agreed to 'release' three industrial, scientific and medical waves for telecoms business.

These three bands, called 'garbage bands' (900 MHz, 2.4 GHz, 5.8 GHz), are allocated to devices used for non-communication purposes, such as ovens. The microwave uses radio waves to heat food. The FCC has put these bands for communication purposes on the basis that any device that uses those bands must walk around to avoid the impact of access from other devices. This is done by a technology called broad spectrum (which was developed for US military use), capable of transmitting radio signals over a range of frequencies, different from the traditional method of transmitting on a single frequency single numbers are clearly defined.

Merge criteria

An important milestone for Wi-Fi took place in 1985 when the process reached a common standard that was started. Earlier, wireless equipment vendors for LANs such as Proxim and Symbol in the United States developed proprietary products, meaning the company's equipment could not be contacted by other vendors. Thanks to the success of Ethernet wired networks, some companies began to realize that establishing a common wireless standard is important. Because consumers will then easily accept new technology if they are no longer confined to a company's products and services.

In 1988, NCR, which wanted to use the 'garbage' band to connect wireless teller machines, asked their engineer, Victor Hayes, to understand the common standard. He, along with expert Bruce Tuch of Bell Labs Research Center, approached IEEE Electrical and Electronics Engineers, where a subcommittee named 802.3 established the current standard Ethernet local area network. . A new subcommittee named 802.11 was launched and the process of negotiating the integration of standards began.

The dispersed market at that time meant it took a long time for different product suppliers to agree with the standard definitions and set a new criterion with the approval of at least 75% committee member. Finally, in 1997, the subcommittee approved a basic set of criteria, allowing 2 Mbps data transfer, using one of two frequency band technologies, frequency hopping (avoiding interference by switching continuous between radio frequencies) or direct-sequence transmission (signaling over a long range of frequencies).

The new standard was officially issued in 1997 and engineers immediately began studying a sample device compatible with it. Then there are 2 standard versions, 802.11b (operating on the 2.4 GHz band) and 802.11a (operating on the 5.8 GHz band), which were approved in December 1999 and January 2000 respectively. After the 802.11b standard, companies began developing devices compatible with it. However, this set of criteria is too long and complicated with 400 pages of documents and compatibility issues still stand out. Therefore, in August 1999, 6 companies including Intersil, 3Com, Nokia, Aironet (later merged by Cisco), Symbol and Lucent joined together to create WECA Wireless Ethernet Compatible Alliance.

Find a suitable name

The operational objective of WECA is to certify that products of suppliers must be truly compatible with each other. However, terms like 'WECA compatible' or 'compliant with IEEE 802.11b' are still confusing for the whole community. New technology needs a convenient way to call consumers. Experts recommend some names like 'FlankSpeed' or 'DragonFly'. But it was finally accepted to call 'Wi-Fi' because it sounds both high-quality (hi-fi) technology and more consumers are familiar with the type of concept like the CD player of any company. It is also compatible with other amplifier amplifiers. So the name Wi-Fi was born. An explanation of 'Wi-Fi means wireless fidelity' is thought of later. Recently, many experts have also stated that Wi-Fi is actually just a name that is easy to call and doesn't mean anything at first.

Going to life

Thus, the wireless localization technology has been standardized, uniformly named and it is time to need a champion to promote it in the market. Wi-Fi has found Apple, a computer maker famous for its radical innovations. 'Apple' claims that if Lucent can produce an adapter for less than $ 100, they can integrate a Wi-Fi slot into every laptop. Lucent met this and in July 1999, Apple announced the arrival of Wi-Fi as an option on their new iBook line, using the AirPort brand. This has completely changed the wireless network market. Other computer manufacturers immediately massively followed. Wi-Fi is rapidly approaching household consumers in the context of technology spending in businesses that are being restricted in 2001.

Wi-Fi then continued to be driven by the strong popularity of high-speed broadband Internet connectivity in households and became the easiest way to allow multiple computers to share a tape access path. wide. As the technology grows larger, toll-free access points called hotspots also begin to appear more and more in public places like shops, hotels, and cafes. Meanwhile, the US Federal Communications Commission (FCC) once again changed its regulations to allow a new version of Wi-Fi called 802.11g to be released, using a more advanced broad spectrum technology. These are called orthogonal frequency-division multiplexing (OFDM) and can reach speeds up to 54 Mbps in the 2.4 Ghz band.

The way forward

Wi-Fi enthusiasts believe that the technology will bypass other wireless connectivity techniques. For example, they argue that hotspot access points will compete with 3G mobile phone networks that promise high-speed data transmission. However, such deductions have been exaggerated. Wi-Fi is just a short-wave technology and will never be able to provide the same scalability as mobile networks, especially as these networks are growing stronger in scale thanks to services. roaming (roaming) and inter-national billing agreements.

However, in just a few years, the first generation of networks based on new WiMax technology, or technically called 802.16, will be available and become popular. As the name of this network shows, WiMax is the large coverage version of Wi-Fi with maximum throughput of up to 70 Mbps and long range up to 50 km, compared to 50 m of Wi -Fi today. In addition, while Wi-Fi only allows access in places where there are fixed hotspots (like public phone boxes), WiMax can cover a whole city or provinces like an electrical network. mobile phone.

At this time, Wi-Fi is the dominant network technology in families in developed countries. TVs, recorders, recorders and many household electronic devices that can use Wi-Fi are appearing more and more. That allows users to transfer content across indoor devices without wires. Wi-Fi wireless phones are also available in offices, but in the long run, this wireless access technology seems hard to be the winner in the long-distance race on these devices. Currently, Wi-Fi consumes a lot of power on handheld devices and even, 802.11g cannot support more than one video stream. And so a new standard, 802.15.3, or WiMedia, has been promoted to become a short-range standard for high-speed home networks, primarily for entertainment equipment.

The development of Wi-Fi technology has also shown that unifying a common standard can create a new market. This is further confirmed by the determination of companies promoting WiMax standards. In the past long-range wireless networking technologies were manipulated by large companies with their own proprietary standards and none was widely accepted. Thanks to the success of Wi-Fi, the giants now work together to develop WiMax, a popular consumer-accessible standard that developers hope to help open. broad market and increase revenue. It's hard to predict the future of Wi-Fi, but it certainly has created a direction for many other technologies.