The new ‘Superspeed USB’ spec hits the home stretch and clocks a clear 10x boost over USB 2.0, although Intel has dropped optical interconnects from the recipe.
USB 3.0 is racing towards the finish line. The current draft spec is expected to be signed off by the end of this year, and within 12 months we’re likely to see the first Superspeed USB kit his the shelves.
It’s a fast pace for the equally fleet-footed technology, which is the third revision since USB made its debut a little over a decade ago. And while USB lost out to FireWire in the sexy name stakes, USB 3.0 has a swanky marketing moniker all its own – Superspeed USB – plus a fresh-baked logo to match.
Driving the Superspeed USB brandwagon is the increasing prevalence of HD Video files and solid state memory, along with consumers’ expectations that USB 2.0 is simply not fast enough.
“Our research shows that about 1.5 minutes after initiating a (file transfer) transaction the general consumer gets frustrated and thinks the application is broken, and will attempt to terminate the application” says Jeff Ravencraft, technology strategist with Intel and Chairman of the USB 3.0 Promoter Group during a presentation at Intel’s IDF techfest in Taiwan. “They expect technology to do much, much better for them.”
Superspeed USB promises to do it ten times better, says Ravencraft, delivering at least 300MB/s compared to the 30MB/s of USB 2.0. In a demo conducted for APC on the industry’s first Superspeed USB host controller a 6GB video file hit a sustained transfer rate of 320MB/s. The gains are less noticeable with a folder chock-full of assorted smaller files, however, as the smaller data packets contain a higher proportion of overhead, dropping the speed back to around 50MB/s.
None the less, even a 1GB video file – the typical size of an hour’s worth of downloaded TV ripped at HD – will scoot through in just over three seconds compared to half a minute on USB 2.0. That’s a blink-and-you-miss-it speed at which it becomes feasibly to load up your portable video player or netbook with ‘grab and go’ content just before you walk out the door, especially if it uses solid state memory.
“USB 2.0 is more than adequate for most of the products in the market today” admits Ravencraft, “but the market doesn’t stand still, and nor does technology. Superspeed delivers the bandwidth and headroom for flash-based products, and will provide headroom for continued growth the next five years. Hard drives will get some benefit from USB 3.0 but they’re based on spinning media and that can only spin so fast. For solid state media the transition from USB 2.0 to USB 3.0 is like going from a propeller plane to a jet plane. Any device that uses an SSD will take full advantage of Superspeed USB.”
While the Superspeed USB cables and connectors retain backward compatibility with USB 2.0, Intel has stepped away from initial plans to use an optical interconnect for USB 3.0’s digital autobahn. A spokesperson at IDF’s Superspeed USB demo area told APC that optical was dropped due to the increased price of the cabling, connectors and the termination cost at each end of the line compared to conventional cable. Optical would have delivered even higher speeds but the current rate of USB 3.0 was “good enough” without raising the technology’s overall cost to manufacturers and thus consumers.
USB 3.0 ports a similar physical format to USB 2.0 but are divided into two physically separate components: one has the same footprint as USB 2.0 plugs, but an extra set of electrical contacts provides the additional uplink and downlink data pathways for a USB 3.0 signal.
The 1.0 spec for Superspeed USB is currently in the release candidate stage undergoing final review, according to Ravencraft, with sign-off from the USB 3.0 consortium by the end of this year.
“Product development is already underway” Ravencraft told APC. “We expect controllers will be available mid-2009 and those will be put into end-user products that we anticipate entering the market for purchase in stores in early 2010, so broad deployment will take off in 2010 and through to 20011. But it wouldn’t surprise me if some companies get aggressive and try to push some product out by the end of 2009.”David Flynn attended IDF Taipei 2008 as a guest of Intel.