Will Apple switch?

Katagiri of NEC said Apple could be forced to switch from Firewire to USB 3.0since Intel is now its major silicon supplier and will be using USB 3.0 eventually in its chip sets.

Nevertheless, USB 3.0 has its challenges. Katagiri said the spec probably will have to reduce the five-meter reach of USB 2.0, perhaps to as little as two meters. In addition, host controllers will have to have significantly more intelligence because they manage routing of data transmissions.

On the other hand, the USB 3.0 group is looking at new techniques for supporting isochronous data transmissions that could provide an edge over features found in Firewire, he added.

For its part, the 1394 has been studying use of Firewire over distances as great as 100 meters on Category 5/6 cable and optical fibre, Snider noted. It is also exploring versions for use in the home and car over coax cables.

Whether the USB group can leapfrog the throughput, quality of service and time to market of 1394 remains to be seen. Many of the same participants running the USB 3.0 initiative also oversee the wireless USB work based on ultrawideband.

"We have a lot on our plate," said Ravencraft who leads both efforts for Intel.

The wireless USB initiative announced today its targets for a version 1.1 of its specification. The new version raises throughput targets from 480 Mbits/second to 1 Gbit/second over three meters.

Katagiri of NEC said the throughput targets are a stretch because most companies are still shipping first-generation wireless USB devices only hitting rates of 40 Mbits/second.

"We have to make the protocol more efficient," Katagiri said. "If we go for a Gbit we will need to deliver at least 500 Mbits/s," he added.

The 1.1 spec will support band groups at 6 GHz and above in addition to the 3-4 GHz bands supported by wireless USB 1.0. It aims to lower power consumption by an undisclosed amount. It also will adopt the techniques of near-field communications for letting two devices identify themselves to each other with a simple contact.

Currently the USB Implementers Forum has certified a handful of notebooks and hubs for the 1.0 spec. The WiMedia Alliance is expected to certify the first 1.0 products shortly.