We take a look at what comes next for
the most common of connection technologies.
USB first hit motherboards back in 1996,
during the reign of Windows 95. It was designed as a next generation
replacement for the serial and parallel interfaces of the time. Unlike these
connections, which required the PC to be rebooted every time a peripheral was
connected, USB was hot pluggable. It could also deliver power, meaning that
small devices didn't need external power bricks to operate.
But more than this, USB was the first in a
raft of new technologies designed to endure the test of time. At that point in
the PC's evolution the original round of interconnect technologies were being
hacked and tweaked to deliver speeds that were never intended. This led to a
rethink of the way in which such technologies were designed, with a shift in
focus to building technologies that could be evolved over time but still stay
compatible with previous versions.
USB was the first, and then came such
things as Serial ATA and PCI- Express. There is no electrical reason why you
can't plug a first generation USB device into the latest USB 3 port (though
there will undoubtedly be driver issues) and it is this backwards compatibility
that has allowed USB to flourish since its launch.
By ensuring compatibility, product
manufacturers have been able to implement new versions of USB fairly easily. It
has also meant that motherboard and system manufacturers have been able to be
proactive, using third party controller chips to add new functions while they
wait for Intel to integrate the technology in its chipsets. Intel has only
added USB 3 support recently, with the Z77 and similar Ivy Bridge chipsets, yet
we've been seeing motherboards and laptops with the tech for two years, and the
connection is now commonplace on external storage devices.
Now that Intel systems have at least four
USB 3 ports by default, we should start to see it flow out onto other devices.
We've seen a Gigabyte keyboard with USB 3 pass through, and our video producer
raves about his USB 3 card reader. External Storage may seem like the best use
of the bandwidth but we expect more and more creative usage to emerge.
USB's ubiquity is its major strength when
it comes to the rate of uptake. Take its most recent competition, Thunderbolt,
for example. To use a Thunderbolt device you need a computer with a Thunderbolt
port, which means a selection of Apple products and an even smaller selection
of very new Windows PCs. A USB 3 device will work, albeit slowly, on anything
with a USB port.
While there is no USB 4 on the horizon,
there are still a few tweaks in the pipeline, aimed at USB 3. The first aims to
maximise the transfer speeds seen with USB 3, and the second is aimed at
evolving its use as a power delivery mechanism.
Since
its launch in 1996 USB has become commonplace.
USB Attached SCSI Protocol
Designed to enable much faster transfer
from external storage. USB Attached SCSI Protocal (UAS) is designed to allow
SCSI commands to be sent over USB. Normally when USB transfers data it does so
using what is known as a bulk transfer. This is where both the data and any
accompanying commands are sent as a single stream of 64k blocks, which was fine
for the relatively low bandwidths of USB 1 and 2, but delivers speeds
noticeably slower than the 5Gbps maximum of USB 3.
What UAS does it bump up the number of
these streams, while also decoupling the commands and putting them into their
own stream. This not only increases the bandwidth available for transfers but
it also means that commands don’t slow down data, and vice versa. This results
in noticeably faster transfers, with speeds limited by the storage device, not
the cabling.
USB
Attached SCSI Protocol
Of course, this comes with a pricetag. UAS
will only work if every part of the data transfer chain supports it. That means
your PCs hardware and software, as well as the device being connected. The
software side is supported in Windows 8, while motherboard manufacturers have
varying levels of hardware support the technology.
As for devices, they are limited to a
handful of external storage products for now, but with Windows 8 bringing
support on the host side we expect to see the number increase over the coming
months. If you want a glimpse into the potential inherent in UAS, some USB 3
devices come with software that enables Turbo mode. This isn’t UAS, but is
rather a means of increasing the size of data packets sent by USB to get around
the problems inherent with 64k block transfer.
You’ll be able to properly use UAS once
Windows 9 launches, as long as you have a supporting motherboard and USB drive.
Power
One aspect where USB has shone is power
delivery. It has now become the international standard for mobile phone
charging (Apple excepted), and there are numerous devices designed to use a USB
cord plugged into a wall adapted for charging.
In fact, there is already functionality
built into USB that allows clients to detect whether they are connecting to a
USB port for data or if it is purely for delivering power. The device can then
draw power based on this information, which is why some tablets will transfer
data to a PC but only actually charge when connected to a wall outlet.
The actual power delivery ability of a PC
based USB port is pretty low, at only 4.5W in USB 3. This is enough to power
laptop hard drives for example, but larger drives need external power to run.
There are some laptops and motherboards that come with special ports designed
to push extra power for device charging, but even these provide just enough
power to charge handheld devices.
This trickle is about to become a flood, as
the USB implementers Forum has recently finalized the USB Power Delivery
specification. This document outlines new standards for USB to deliver up to
100W of power, ten times the output of Intel’s Thunderbolt technology.
While 100W USB will make charging phones
and tablets a snap, its real intention is to facilitate new usage and charging
models. It commonly-used example is a monitor or dock that uses USB to charge
your laptop when you get home. It has potential to reduce the need for power
boards and multiple adapters in our computing lives – your monitor, printers
and other devices could all be powered by the cable connecting them to your PC.
As to when we’ll see this standard hitting
actual products, it could still be a while. It was only finalized in July this
year, and it is likely that actual implementation will take months to happen,
and even then it won’t appear in products until next year.
What about syncing?
One area in which USB’s days seem to be
numbered is syncing devices. At the moment USB is commonly used to get data
onto mobile phones and tablets, but this is likely to become less important as
the next generation wireless standard, 802.11ac, rolls out.
802.11ac offers gigabit transfers speeds,
which not only means that data transfer is fast, but it delivers huge power
savings thanks to the wireless radio needing to operate a fraction of the time.
It is expected that when phones and tablets with 801.11ac begin to appear
(early 2013 at CES is a good bet for when this will happen), that they will be
the first generation of products designed to have Wi-Fi turned on permanently.
Once this happens, wireless syncing becomes more and more useful, so don’t be
surprised if your USB cables end up being used for power delivery only.
