Is Your USB 2.0 Device Really Just USB 1.1?
By
Mike Pasini, The Imaging Resource
(Thursday, June 19, 2003 - 12:27 EDT)
Whether you are buying a card reader or a digicam with a USB interface, the 2.0 tag does not mean the device runs at high speed.
Since the introduction of USB 2.0, featuring transfer speeds as high as 480Mb/s, the protocol has been confused solely with its high-speed variant. In fact, according to the 2.0 specification, it encompasses three speeds: low (1.5Mb/s), full (12Mb/s) and high (480Mb/s).
"The correct nomenclature for high-speed USB products is 'Hi-Speed USB.' The correct nomenclature for low or full-speed USB products is simply 'USB,'" according to USB.org's SB Naming and Packaging Recommendations.
While the document cited above is intended for manufacturers, the packaging keys and messages will be of interest to any consumer shopping for a USB device. High-speed devices can be identified, for example, by a different USB logo, featuring a red "Hi-Speed" flag over the blue Certified USB logo.
The confusion over the specification was recently noted in a Bangkok Post article that spurred some discussion at Slashdot.
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