The USB Promoter Group yesterday released the draft specification for USB 2.0, taking the target data transfer rate up to 480Mbps, a fortyfold increase on the current version's throughput. Released to delegates at the USB Developers Conference, the new spec. calls for full compatibility -- forward and backward -- with USB 1.1, so at least no one is going to have to chuck out their old peripherals. The USB Promoter Group clarified its stance on IEEE1394 (aka FireWire and iLink): USB 2.0 will become the be all and end all of PC connectivity and 1394 will continue to exist in the consumer electronics space, connecting digital VCRs to digital TVs and the like. In the USBPG worldview, the only PCs that require 1394 will be those that need to connect to such devices -- all other high bandwidth devices, such as fast hard drives, will clearly be hooked up via USB 2.0. As the Technical Introduction to USB 2.0 puts it, even "high bandwidth interfaces such as SCSI adapters may no longer be required". So where we once had 1394 replacing SCSI while USB replaced the old serial and parallel ports, we now have USB 2.0 replacing everything. USB 2.0 is unlikely to supersede 1394, though, since it retains the need for a hub -- unlike 1394, there's no peer-to-peer operation; data can only from device to device via the hub. In fact, hubs will take on a greater role with USB 2.0 since they will have to arbitrate data traffic flowing at 480Mbps and the original 12MBps and 1.5Mbps. At least in the draft spec. there appears to be no plans to change this hub-based mode of operation, or to increase the number of devices the chain can support. Now the draft specification is in place, peripheral developers are at last able to map out their support for the technology. The final version of the USB 2.0 spec. is due sometime in the first quarter of next year, with the first devices using it coming to market in the second half of 2000 after volume production of USB 2.0 chipsets has been reached. ®