USB just got faster

USB stands for Universal Serial Bus and it is truly universal. Almost every computer on the planet sports at least one USB port and the technology is so popular it has spread to games consoles, phones and other related gadgets.

Contrary to popular myth, USB technology is not new; it has been with us for about 15 years, meaning younger and new computer users will have no idea just how revolutionary USB was back then.

But it wasn't just USB that changed how we used computers - that was more down to the devices that made use of it.

USB was designed to replace the motley array of ports that had become the default configuration for "IBM clone" computers. Back then, the only means we had of attaching and communicating with external devices were serial (com) and parallel (lpt) ports, both limited in what they could do.

Those with longer memories may recall the days before "plug and play" systems, ("plug and pray" I called it), where such ports were configured by manually assigning memory resources and interrupt requests.

Many a recurring migraine disappeared the day USB made it possible to hot-plug a device and the operating system simply picked it up and ran with it. Kids today just don't understand.

Most USB-connected peripherals today are designed for what is known as USB 2. Early USB was labelled USB 1, then USB 1.1. The technical differences are too tedious to cover here, but taking into account the new-fangled USB 3, we can label them Fast, Faster and Fastest.

Early USB 1 flash/thumb/pen drives may have been revolutionary and a vast improvement over floppy disks (not only in transfer speed, but in reliability and usability) but they are actually slow compared to USB 2 devices, as anyone copying files to or from one can attest.

Everyone understands numbers, so let's look at some:

The maximum theoretical data rate for USB 1 is 12 Mbps (that's megabits per second - divide by eight to get megabytes per second). Confusingly, that standard also allowed a lower transfer rate of 1.5 Mbps for the likes of game controllers and joysticks. Compared to floppy disk's mundane 1 kilobits per second, this was rocket-ship fast.

For some reason it took much gnashing of teeth and wringing of hands to develop the USB 2 standard, introduced in 2001-02. This bumped the data transfer rate up to a whopping 430 Mbps - 40 times that of USB 1. Fortunately, (and unusually in the computer world), most devices are backward compatible - that is, you can run a USB 2 device in a USB 1 port, though some may not work very well should they rely on the higher transfer rate for proper operation. Later versions of Windows will let you know if the device you plug into a USB 1 port can go faster.

We are starting to see USB 3 ports filtering through in new motherboards and peripherals. Again, there was much hoo-hah over creating USB 3, but compared to USB 2, it is FAST. Electronic jiggery-pokery means that throughputs of up to 5 gigabits a second are possible, though 3.2Gbits/s is more typical in real-world use.

One potential problem is USB 3 connectors differ slightly, meaning backward compatibility is not guaranteed. Hardware buyers should check carefully before taking the plunge. USB 3 drivers are increasingly available for existing hardware; check product websites and Microsoft for Windows support.

Dave Thompson runs a computer-services company in Christchurch.

- © Fairfax NZ News