Peer-to-peer USB 2.0 spec. washed in public
Supporters eye 1394's hold on consumer electronics industry
The USB Implementers Forum, the consortium of developers behind the Universal Serial Bus, has just issued the first public version of a specification designed to allow the bus to offer IEEE 1394-style peer-to-peer connectivity.
Extending USB to circumstances where there isn't a host PC to manage the bus is a pretty radical move, and one that has clearly been made to drive USB 2.0 into 1394's consumer electronics heartland.
After all, USB 2.0 hasn't exactly had a ringing endorsement from the PC business. There are moves afoot to get it onto Linux, but that seems as much an attempt to support a technology not yet supported by a Microsoft operating system as a major thumbs-up for the bus from the open source community. Intel is still very keen on USB 2.0, but with Windows XP support still some way off, even it feels the need to talk up 1394.
Indeed, had USB On-the-Go not been in the works for most of 2001, we'd be inclined to wonder if it wasn't an attempt on the USBIF's part to prevent USB 2.0 becoming Bluetooth to 1394's 802.11 - a once promising technology now apparently superseded by a more popular alternative.
In fact, On-the-Go was proposed earlier this year by host controller silicon developer TransDimension. Now, as then, On-the-Go will be offered as a supplement to the USB 2.0 specification.
On-the-Go defines not only a new, smaller connector for mobile devices, but portable-oriented power-preservation features and "limited host capability to communicate with selected other USB peripherals", as the USBIF puts it.
That's still not as flexible as 1394's peer-to-peer facilities, but it's a start. Probably the end, too, since the USBIF's reference to "selected" USB devices suggests that while On-the-Go may be touted as a way of allowing MP3 players to share files (not that the Recording Industry Ass. of America is going to be very keen on that) and cameras to dump pictures straight to a printer, the Forum doesn't want to sideline the PC too far.
The On-the-Go spec. is currently at version 0.9. After a period of public consultation the USBIF hopes to draft a final 1.0 specification by the end of the year. ®