Science and Technology Wimax

The internet celebrates a landmark event on the 15 March - the 25th birthday of the day the first dotcom name was registered.
In March 1985, Symbolics computers of Cambridge, Massachusetts entered the history books with an internet address ending in dotcom.
That same year another five companies jumped on a very slow bandwagon.
It took until 1997, well into the internet boom, before the one millionth dotcom was registered.
"This birthday is really significant because what we are celebrating here is the internet and dotcom is a good, well known placeholder for the rest of the internet," said Mark Mclaughlin, chief executive officer of Verisign the company that is responsible for looking after the dotcom domain.
"Who would have guessed 25 years ago where the internet would be today. This really was a groundbreaking event," he said.
Commercialisation
For most of the late 1980s and early 1990s hardly anyone knew what a dotcom was. Scholars generally agree that a turning point was the introduction of the Mosaic web browser by Netscape that brought mainstream consumers on to the web.With 668,000 dotcom sites registered every month, they have become part of the fabric of our lives.
Today people go to dotcom sites to shop, connect with friends, book holidays, be entertained, learn new things and exchange ideas.
"Dotcoms have touched us in a way we could not have imagined," Robert Atkinson of the Information Technology and Innovation Foundation (ITIF) told.
"It used to be, 10 years ago you could live an okay life if you weren't engaged on a dot com site on a daily basis. You could get what you needed.
"But today we see how dotcoms have enriched our lives that if you are not engaged you would be fine but much further behind than the rest of us."
Proof of that Mr Atkinson said can be seen with how dotcoms have commercialised the internet "bringing consumers choice and value and businesses greater customer reach and profits".A study by the ITIF claims that "the average profitability of companies using the internet increased by 2.7%".
The research also found that the economic benefits equal $1.5 trillion, which it says is "more than the global sales of medicine, investment in renewable energy and government investment in research and development combined".
By 2020 the internet should add $3.8 trillion (£2.5trillion) to the global economy, exceeding the gross domestic product of Germany, it found.
The future
An estimated 1.7 billion people - one quarter of the world's population - now use the internet.
Verisign's Mr McLaughlin only sees that figure growing over the next quarter of a century.
"I think that the way we access information today, mostly still through PCs and laptops is highly likely to change; that the voice will be more important than text input.
"I think the whole fabric of how we access, search, find and get information is going to be radically different."
At the moment Verisign logs 53 billion requests for websites - not just dotcoms - every day, about the same number handled for all of 1995.
"We expect that to grow in 2020 to somewhere between three and four quadrillion," Mr McLaughlin told.
One quadrillion is 1,000 billion.
It is a phenomenal pace of growth that would have been very difficult to predict 25 years ago when a small computer firm took the first pioneering steps into the connected world.