Inside USB 3.0
What makes SuperSpeed tick
NEC last week announced what it claims is the world's first host controller chip for USB 3.0 - aka SuperSpeed USB because of its 5Gb/s peak data-transfer rate.
Since the Universal Serial Bus isn't a peer-to-peer system - unlike Firewire, for instance - NEC's chip isn't enough to allow manufacturers to offer USB 3.0 peripherals yet, but once the part ships - it's due next month - they will be able to prepare SuperSpeed PC designs.
NEC reckons that after releasing small, 'sample' quantities of the chip in June, it'll ramp up production to significantly larger volumes in Q3, allowing computer makers to take those designs and put them on shop shelves. There may not be many - or even any - SuperSpeed peripherals to hook up to these machines.
Whether you dive in to USB 3.0 as soon as you can or wait until there are plenty of devices out there than can take advantage of it, the move from USB 2.0 to USB 3.0 should be as smooth as upgrading from USB 1.1 was.
But USB 3.0 is something of a departure from 2.0 from both technical and practical standpoints, and while the minds behind the new standard have made backward compatibility a cornerstone of their development efforts, USB 3.0 is not simply a higher-clocked USB 2.0.
USB 3.0's raison d'etre is to up data-transfer rates to ten times what USB 2.0 can manage, jumping from 480Mb/s to 5Gb/s, needed now we're throwing HD video files around. Error handling and the needs of the data-transfer protocol will reduce that some, just as it does with 2.0, but the new bus nonetheless justifies its 'SuperSpeed' moniker.
What goes into USB 3.0
Achieving that data rate has required some hardware changes. Skinny, unshielded cabling that's fine for USB 2.0 is out, replaced by shielded, multi-core wires-within-wires - Shielded Differential Pair, or SDP - cables, which will be thicker than those we're used to. Shielding is needed to cut out the electromagnetic interference that reduce the signal integrity and prevent the bus from achieving that 5Gb/s throughput. You simply can't do SuperSpeed over USB 2.0 cabling.
Adaptive equalisation circuitry in each device helps it all along. AE allows the state of the connection to be measured and the electrical signal altered to optimise data delivery over that particular physical connection, compensating for differing lengths of cable and different quality wiring.
COMMENTS
@ Simon Ward & unexpected Bill
They should follow unreal tournaments announcements
I think it should go Monster Speed followed by Godlike
By the time USB 3.0 ports are to be found in netbooks, they'll be running Windows 7 anyway -NOT!
Windows 7 will not run on Netbooks - MS say Netbooks dont exist - especially the really fast ones running arm chips!
Whatever it is trying to be I'm fairly sure wireless is a much more sensible way to go - nothing new to do there - I don't want cables FULL STOP.
@Eddy Ito: connector standards
I think the reason for the backwards compatible connector is not for devices but for hosts.
Suppose USB3 has different connectors and suppose you are an OEM designing a netbook. There is only room for three ports. What combination do you choose? On one end of the spectrum will be power users who want to plug in loads of USB3 devices, and have hubs and adapters for any legacy USB2 devices, at the other end is the road warrior who has left his USB2 to 3 adapters at home and wants to plug in a USB2 mouse, thumb drive and printer.
With backward compatible connectors you don't have that dilemma. All the ports can be USB3 compatible (if the chipset allows it) and everyone is happy.
@Simon Ward
Regarding "What are they going to call USB4.0? 'Ludicrous Speed'?"
How about "On Speed"?
The only thing I want.
Is for a return to the original ethos of plug-and-play (and-unplug) and not what we have at the moment of plug-and-play then arse-about-stopping-the-device-waiting-a-bit-for-Windows-to-do-it's-thing-and-tell-you-it's-stopped-and-THEN-unplug.
It's not a lot to ask is it?
