Mobile working Toolkit

400Mbps Wi-Fi standard back on track

Tags:
802.11n,
Wi-Fi,
Mimo

Tom Krazit CNET News

Published: 20 Jan 2006 10:10 GMT

A faster Wi-Fi standard appears to be about a year away, after a task group unanimously approved a proposal for an update to the 802.11g standard.

The 802.11n task group of the Institute of Electrical and Electronics Engineers approved the first draft of the new standard at a meeting in Hawaii on Thursday. Passage of the draft required 75 percent of the group to approve, but the final vote was 184 to 0, with four abstentions. Final ratification of the standard is not expected until next year, and several revisions are expected to take place before that final standard is ratified.

802.11n will allow notebook users to connect to wireless access points at much faster speeds than currently available with 802.11g technology. It will use a technology called MIMO, which allows the chips to use multiple antennas that can each handle more than one data signal at a time. This is expected to improve the range and throughput of 802.11n products to the point where they should be able to send video content around a house without interrupted playback. Products with 802.11n chips will be able to work with older 802.11a/b/g products at their slower speeds.

The draft standard is similar to the one proposed late in the evaluation process by the Enhanced Wireless Consortium (EWC), which consists of companies such as Broadcom, Intel and Linksys. The EWC made a proposal for the 802.11n standard just as two other groups were preparing to merge their competing proposals for the final standard last October.

Broadcom announced Thursday that it was immediately shipping a new group of Wi-Fi chips called Intensi-Fi that is compatible with the draft standard. The company claimed the new chips could provide data rates up to 300Mbps, although real-world speeds are likely to be lower.

Broadcom also claimed that the Intensi-Fi chips would be compatible with the final version of the 802.11n standard through firmware upgrades to products using the chips. This touched off a heated rebuke from Airgo Networks, which already makes chips that use the MIMO technology at the heart of the 802.11n draft standard.

"The only event that consumers can count on to guarantee compatibility is Wi-Fi Alliance certification," Greg Raleigh, chief executive officer of Airgo, said in an interview Thursday.

Usually the IEEE and the Wi-Fi chip vendors reach a point in the draft revision process where everyone feels comfortable that the final standard will not change much further, Raleigh said. At that point, the Wi-Fi Alliance starts preliminary testing of wireless clients and access points, and Airgo will be ready with products that will help kick off that testing, he said. Those products will be upgradeable to comply with the final standard through a software download.

Broadcom believes it has designed its Intensi-Fi chips in such a way that products with the chips will be upgradeable with software no matter what twists and turns the draft proposal takes on the final road to ratification, a Broadcom spokesman said. The company is not guaranteeing that compatibility, however, he said.

Consumers should be wary when purchasing any wireless device that does not bear the stamp of the Wi-Fi Alliance, said Will Strauss, principal analyst with Forward Concepts.

If a home user has two draft-standard chips on both ends of their network, they'll get the advertised performance, Strauss said. But if they try to take a notebook with one of those chips to a coffee shop that's using a Wi-Fi Alliance certified 802.11n access point, they might not get the advertised performance, he said.

Chipmakers that release silicon based on draft standards are essentially making a bet that their products will need only software upgrades to the final standard, Strauss said. That strategy allowed Broadcom to jump out to an early position as a pre-eminent supplier of 802.11g chips, he said.

If it works, the chipmaker has a jump on larger competitors such as Intel, which is forced to wait until the final standard is released because of the scope of its Centrino marketing campaign, Strauss said. But if it doesn't, any chipmaker that comes out with pre-certification products will bear the wrath of their customers, he said.

The Wi-Fi Alliance is expected to begin certifying products in early 2006, Airgo's Raleigh said. Final ratification is expected to follow soon after, he said.