Wireless networking using the 802.11 standard , also known by its trade name , Wi - Fi , has become common in the home and has a important and produce use in corporate circumstance . But the exist touchstone , 802.11 gramme , was sign in 2003 and is increasingly look as poor as applications become more complex and require more bandwidth .

For instance , streaming video — whether it ’s a feature film - length movie at home or videoconferencing at study — is a dicey suggestion with 802.11 g. So - ring “ g ” products have a theoretical maximum throughput speed of 54Mbit / sec . but real - world speeds of half that or even dense , which is n’t quite enough for TV .

To the rescue , finally , will be 802.11n , which promises importantly higher speed and grasp . Here ’s the lowdown of what to expect with 802.11n and when to bear it .

Already , Apple is embark 802.11n - establish devices . Its raw AirPort Extreme Base Station supports a draft specification of 802.11n , and the capability has been exposed in several of its Mac models .

How is 802.11n dissimilar than current generations of Wi - Fi ?

The 802.11n touchstone uses some new technology and tweaks be applied science to give Wi - Fi more speed and range . The most notable new technology is called multiple input , multiple output ( MIMO ) . MIMO employ several antennas to move multiple data current from one place to another . rather of sending and receiving a undivided flow of data , MIMO can simultaneously broadcast three watercourse of data and receive two . This permit more datum to be channel in the same period of clip . This proficiency can also increase range , or the distance over which data point can be transmitted .

A second technology being incorporated into 802.11n is TV channel bonding , which can use two disjoined nonoverlapping TV channel at the same meter to transmit data . This technique also increases the amount of data that can be broadcast . A third technology in 802.11n is call payload optimization or packet collection , which , in simple terms , means more data point can be choke up into each transmit packet .

So , what are the benefits of 802.11n ?

Users will mark two thing about this Modern and improved wireless technology : significantly not bad amphetamine and scope . Both Intel , which has a vested interested in 802.11n because it manufactures wireless scrap sets , and independent reviews indicate that the title of greater f number and kitchen stove for 802.11n are true .

Specifically , 802.11 GB products , which have a theoretic maximal throughput speed of 54Mbit / sec . , typically provide material - world speeds of 22Mbit / sec . to 24Mbit / sec . In contrast , Intel says it ’s seeing real - mankind speeds of 100Mbit / sec . to 140Mbit / sec . for 802.11n equipment . Those results were affirm in a recentComputerworldroundup reviewof several Wi - Fi ware based on Draft 2 of the 802.11n standard .

Range is harder to quantify because it ’s affected by many variables , such as barrier that could block the signal . However , Intel reports that 802.11n equipment typically delivers more than twice the stove of 802.11 M equipment , at any give throughput speed . Those results were confirm anecdotally in the recent Computerworld review .

“ At the very remnant of an open field with no interference , where you could get 1Mbit / sec . with “ GB ” equipment , you ’ll final 14Mbit / sec . to 16Mbit / sec . with “ n ” equipment , ” cover Ashish Gupta , an Intel mathematical product managing director .

What ’s in it for business users ?

consumer are increasingly buying equipment base on rough drawing adaptation of 802.11n . However , few line of work will deploy 802.11n products until the criterion is to the full ratified and business enterprise - focused marketer such as Cisco Systems offer intersection base on the ratified standard . When that happens , however , the part of wireless networking is expected to importantly increase in corporate options .

Wireless networking in many caller often fill up specific recess , such as providing networking in conference rooms , lunch suite or in temporary or under - construction office space . That lack of full deployment of radio is intelligible given that Ethernet supply greater reliability and f number ( theoretic uttermost of 100Mbit / sec . ) and is switched , while wireless LANs volunteer slower speeds and the bandwidth is shared . The fresh 802.11n engineering will work the throughput problem for business users , opening the way to far more applications , such as wireless voice over IP and more videoconferencing .

And what about consumers ?

The increased compass of 802.11n will imply few “ dead spots ” in menage served by a single Wi - Fi router . It also will launch the mode to high - bandwidth program such as stream television from , say , screen background computers that store video to Wi - Fi - enabled TV . The novel criterion will also be more dependable for voice - over - IP and , in general , for multiple users doing multiple thing over the mesh .

Does the new standard have new surety capabilities ?

No . While Wi - Fi once was considered quite unsafe , most current - propagation products now corroborate Wi - Fi protect Access ( WPA ) and WPA 2 for encoding and authentication , which allow for strong protective covering for wireless networks .

However , the Wi - Fi Alliance , the trade organization for Wi - Fi vendors , is institute a specification aimed at make security easier to deploy by home users . The program , called Wi - Fi Protected Setup , enable apparatus of WPA or WPA 2 just by push buttons or entering personal identification numbers . This program is not part of the 802.11n touchstone , but equipment vender are start to deploy it just as Draft 2 Wi - Fi product are becoming common .

Why is ratification of 802.11n taking so long ?

The 802.11n touchstone is being developed by a working group of the IEEE . Under the in effect of setting , ratifying an of import new standard is an excruciatingly slow , multiyear process , because work out groups address the smallest subtlety of the standards and discuss different approaches and then sort it all out and vote .

In this case , the confirmation process start more than three years ago . ab initio , there seemed to be concord about one particular approach to meeting the goals of the standard , but a rift developed between vendors that slow down the process even more than usual .

That rift has been resolved . At a March meeting in Orlando , the working mathematical group give formal approving to Draft 2.0 and set as a destination to publish the concluding criterion in October 2008 ( Since then , the date for ratification has been pushed back to March 2009 ) . The draft received more than 80 pct favorable reception among voters in the chemical group ; 75 percent was required for approval . That indicates that there was a high level of consensus and that there probably will be few , if any , essential change between Draft 2 and the final , ratified variation of the banner . However , a Draft 3.0 still must be approved , which will deal with Wi - Fi in consumer electronics equipment such as camcorders and media players .

Does that stand for we ca n’t expect 802.11n product until final ratification ?

merchandise free-base on Draft 2 are available now and have meet generally positive review both in term of increase speed and chain and compatibility with old Wi - Fi products . The products are being direct at consumers ; as stated previously , corporate IT shops are unlikely to be concerned until after last ratification of the standard .

trafficker are not making promises , but they are saying it is their hope that the Draft 2 products will be firmware upgradable to the final , ratified stock when it is eventually sanction . After that clock time , endeavour - pore vendors such as Cisco are expected to release 802.11n product .

Are n’t draft-802.11n product being certify by the Wi - Fi Alliance ? If so , what does that imply ?

The Wi - Fi Alliance is a trade organization made up of Wi - Fi vendors ; it is not a standard - set trunk . However , because the standard - fix process can be long and tortuous , Wi - Fi equipment marketer were queasy to release next - multiplication mathematical product . There were frequent report that product based on Draft 1.0 had problems interoperating with older Wi - Fi product and with other Draft 1.0 products . However , products found on Draft 2 seem to be more reliable and interoperable .

To make certain that ’s the example , the Wi - Fi Alliance will go certify products found on Draft 2 this summer , testing for interoperability and compliance with the draft specification . That have in mind that any intersection you corrupt that are attest will be backward compatible with 802.11a / b / g. It is n’t cognise yet , however , whether they will be onwards compatible with products based on the ratified standard .

In addition , Intel is supporting Draft 2 802.11n technology in its Centrino flake sets . Vendors of equipment such as router will be earmark to put a logo on their packaging indicating that those products work with the Intel power train .

David Haskin is a contributing editor specializing in mobile and wireless yield .