Wireless USB and USB 3.0

This TekSpek explains what Wireless USB and USB 3.0 are, how they work, where you'll find them, and what the future holds for the Universal Serial Bus specification.

The Technology and how it works

Universal Serial Bus (USB) was originally introduced in 1995 by Intel, Microsoft, Philips, and US Robotics as a means to allow various peripherals to be connected using a standardised interface socket. It led the way for improved plug-and-play capability and allowed devices to be connected and disconnected from a computer without the need for a reboot.

USB also carried the benefit of being able to provide power through its standard interface. By doing so, many devices were able to function with a USB connection alone, removing the need for an external power supply.

Since its introduction in 1995, USB has become the most commonly-used interface in computing and in 2004, an estimated one billion USB devices were available in the world.

Its continued growth has led to continued development and having launched with a data transfer rate of just 1.5Mbit/s over ten years ago, the USB specification has continually evolved and improved over time.

In 1998, USB 1.1 was released and fixed a number of problems inherent in 1.0. Following that, an initiative led by Hewlett-Packard, Intel, Lucent, Microsoft, NEC, and Philips resulted in USB 2.0 being released in the year 2000.

As the first major upgrade for the USB platform, USB 2.0 offered a significant boost in speed, raising potential data transfer rates up to the then-dizzy heights of 480 Mbit/s.

Today however, the continued growth of HD material, increasingly large file sizes and consumer desire for wireless capability has proven that USB needs to evolve once again.

In 2008, you’ll be hearing a lot more about the next two big changes to USB; USB 3.0 and Certified Wireless USB.

USB 3.0, the successor to USB 2.0, is expected to appear in products from 2009 and its final specification is set to be announced in the first half of 2008.

USB 3.0 utilises a parallel optical cable and is designed to be backwards-compatible with USB 2.0 and USB 1.1 whilst also being more energy-efficient than its predecessors. Though a specific data-transfer rate for USB 3.0 has yet to be confirmed, it is claimed to reach ten times the bandwidth achieved by USB 2.0, meaning potential transfer rates of 4.7 Gbit/s.

Certified Wireless USB, more commonly known as just Wireless USB or WUSB, is a short-range wireless radio communication protocol capable of data transfer rates similar to USB 2.0 (480 Mbit/s) at distances of up to three metres and 110 Mbit/s at distances of up to 10 metres.

In 2005, the Wireless USB Promoter Group (consisting of Agere Systems, Hewlett-Packard, Intel, Microsoft, NEC Corporation, Philips and Samsung) announced the completion of the WUSB specification and now, some three years later, WUSB is starting to appear in consumer devices.

WUSB, though not as fast as USB 3.0, is a technology you won’t have to wait for. It is available today in various devices such as laptops from Dell as well as hubs from D-Link and Belkin.

The aim of WUSB is to provide wire- and clutter-free connectivity to peripherals in the home and around the PC. The ability to connect devices such as printers, mobile phones, cameras and media players to a computer or laptop without wires has immediate appeal to many consumers.

The Players and Competition

It should be noted that USB 3.0 and WUSB don’t have the market entirely to themselves. Though USB is the world’s most commonly-used interface, it faces continued competition from FireWire - Apple’s name for the IEEE 1394 interface. Sony also refers to the interface as i.LINK and Panasonic calls it DV.

FireWire connections are found in the majority of modern digital camcorders and have built a reputation of being better-suited for home or professional audio/video computers due to more-consistent transfer rates than today’s USB connections.

FireWire S3200, the latest FireWire standard to be announced by the 1394 Trade Association, will soon be available in products and is capable of speeds of up to 3.2 Gbit/s. Though not as quick as the forthcoming USB 3.0, FireWire S3200 has the advantage of operating on existing FireWire cables, whereas USB 3.0 users will require new USB cables and connectors to utilise the faster speeds.

WUSB, too, is not without competition as 802.11a/b/g and Bluetooth wireless protocols already exist in today’s market. However, WUSB does target a different audience. With Bluetooth’s maximum transfer rate limited to 3 Mbit/s, it isn’t suitable for devices such as wireless hard drives – WUSB’s 480 Mbit/s is better-suited to the task.

Wi-Fi, too, is slower than WUSB, though able to cover much larger distances. The target for Wireless USB is high-bandwidth devices located within a short range, a market it could well make its own.

Summary

USB is already established as the preferred interface in computing. With WUSB bearing down on us today and USB 3.0 looming just around the corner, expect to see USB continue to dominate and appear on millions more devices.

2008 could well be the year of WUSB and 2009/2010 are looking certain to be the years of USB 3.0.