USB 3.0 : A Primer

USB 3.0 ports will start arriving by the end of this year.
Here's what you need to know.

That Universal Serial Bus port in your computer is about to
get an upgrade. You know, the one where you plug in all your
external hard drives, digital cameras, MP3 players, thumb
drives, and USB heated-slippers? If you bought your computer
any time after the year 2000, it probably came equipped with
a USB 2.0 port. However, later this year computers will
start shipping that include USB 3.0 ports, which can transmit
data up to ten times as fast. Here's what to expect.

What is USB 3.0?

Dubbed "SuperSpeed," USB 3.0 is much faster at transferring
data than its predecessor. The current 2.0 ports can transfer
packets of information at speeds of 480Mbit/s, but the 3.0
spec will be able to handle 4.8 to 5Gbit/s. This tenfold
increase in speed is accomplished by increasing the number of
wires used for transfer from 4 to 9 and more efficient
handling of the traffic throughout the data bus. This large
flow of information can also be split into several different
streams of information being transferred at once.

USB ports can transfer not only information but also
electricity to peripherals, which has yielded many kooky
results. While energy transfer is nothing new in USB ports,
the new version will help conserve energy. As it stands, USB
connections are not specialized, and information packets are
broadcast to all peripherals attached. The new ports and
cables, however, will target the necessary device and send
packets only to the devices that need to receive them. That
allows conservation of power on portions of the cable that
are not being used.

The best part is backwards and forwards compatibility. New
cables will work in old ports (although not with the
increased speed), and old cables will work in new ports. When
confronted with disparate ports and cables, the computer will
initiate polling to decide what the highest speed is that
both ends can support.

What will USB 3.0 do for you?

Of course, there's the increase in speed of packet transfer.
That'll mean faster uploads of photos or MP3s to and from
your cellphone, and drastically better performance for USB
mass storage devices like external hard drives. There's also
the potential for hi-def streaming: 5Gbit/s speeds offer the
ability to cleanly stream video at 1080i definition. The
process is also scalable for any future developments that
Moore's Law will throw our way: USB 3.0 was made in
preparation for future computing.

When will you get USB 3.0?

Taiwanese PC manufacturers claim they will start shipping
3.0-compatible computers by the end of this year. However,
it's estimated that these initial models will only be able to
reach about a quarter of the port's potential speed. The
technology will evolve over time to reach its maximal rates.
Meanwhile, the port will become much more ubiquitous: About
140 million units will be produced in 2011 and up to 340
million units by 2012.