Bluetooth bites into a new opportunity

Whatever happened to the personal area network? It could be due a revival thanks to the proposed merging of Bluetooth with ultra...

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Whatever happened to the personal area network? It could be due a revival thanks to the proposed merging of Bluetooth with ultra wideband radio technology


The decision by the Bluetooth Special Interest Group (SIG) to create a new version of the standard has been applauded by suppliers. It wants to merge Bluetooth with the ultra wideband radio technology to create a new, high-speed version suitable for applications such as video.

This could give a boost to a technology that has largely failed to deliver on its promises since its introduction late in the 1990s.

When Bluetooth first appeared, people asked too much of it, said Bob Heile, one of the founding members of the Institute of Electrical and Electronics Engineers' (IEEE) 802.11 working group on wireless technology which ratified the raft of different wireless Lan standards. "What it basically does is wireless headsets and synchronisation technology."

Heile also chairs 802.15, the IEEE working group on wireless personal area networks, and claims to have invented the term. Remember personal area networks? Back in 2000, everyone was talking about them. Bluetooth was originally going to form the basis for the huge growth in Pans: very localised networks of devices such as cameras, printers, watches and music players.

These devices would connect to each other on an ad hoc basis, enabling information to be exchanged without wires.

Unlike IRDA, which was a line-of-sight infrared technology, Bluetooth's radio system would be able to transfer contact information from the PDA in your pocket to your business partner's smartphone sitting on the restaurant table. If you were in an office, you would be able to send Powerpoint slides to the printer without having to fiddle with USB cables.

At least, that was the idea. Why has the technology decayed to the point where it is more a tool for telecom headset providers than a conduit for Pans?

"To be candid, Bluetooth did not always work that well," said Colin Curtis, research and development manager at networking consultancy Xpert Communications. "Because there have been some interoperability problems and a few standards issues outside of that, it has not taken off."

However, a profile for Bluetooth as a Pan technology has been completed, said John Halksworth, product marketing manager at Cambridge Silicon Radio, which makes Bluetooth components. "It took longer to become mature and stable than was originally thought," he said. "It is there now and Pan just provides Ethernet over Bluetooth. So anything that works with TCP/IP will run over that Pan profile."

There were other contributing factors to the failure of the Pan concept. Wi-Fi technology exploded on to the scene with more force than many people had anticipated.

Its power requirements, range and data throughput are higher than Bluetooth, putting it more in the Lan space than the Pan category, but the value proposition was great enough to overshadow Bluetooth as a wireless technology, leaving the latter little room to establish itself.

The Wi-Fi effect has been compounded by another, more business-focused development. Convergence has been a popular buzzword in the past five years, as consumer technology companies have vied to produce increasingly integrated devices, offering more functions in smaller packages. This has led to the technology equivalent of the multifunction kitchen device. Cameras and MP3 players have been integrated into phones, and phones have been integrated into PDAs. What need is there for a Pan when all the devices are in one box?

The need is still there, according to Tal Raeside, vice-president of marketing and strategic development at IXI, which makes software-based personal mobile gateways (PMGs) that sit in smartphones. The PMG acts as a middleware layer for Pans, minimising interoperability problems between Bluetooth profiles within different devices, and making it easier to transfer data at the application layer, such as the content of your personal information manager.

One of the prototype devices that IXI has worked on with a partner is a watch linked to the phone via the personal mobile gateway. When the phone rings, call line identification shows information about the caller on the watch's screen, and the user can then manipulate the call via the watch, sending the caller to voicemail, for example.

Connecting individual devices through a Pan rather than trying to use an integrated device gives you more flexibility, said Raeside, adding that this can make the use of personal technology within corporate environments more effective.

"Field engineers do not want to use a smartphone because they are not durable," he said. "They can now use rugged devices and access the cellular network through the PMG." In another example, insurance loss adjusters can take high quality pictures using a better digital camera which can then be hooked to a laptop using a PMG, Raeside added.

So, will integration of Bluetooth and ultra wideband lend credence to this idea? Under the agreement, ultra wideband will be grafted on to the Bluetooth protocol, providing a physical layer with speeds high enough to facilitate video transfer between, say, a set-top box and a plasma screen, or a tablet PC and a digital projector.

Ultra wideband is being promoted heavily by the WiMedia Alliance, which joined forces with the Multiband OFDM Alliance special interest group in March 2005. It is being touted as the "can-do" short range wireless technology. According to the merged organisation, we can expect to see transfer speeds of 600mbps plus, as products begin to roll out towards the end of this year, and over time its physical transport layer will also support wireless versions of many popular PC interfaces. Look for wireless USB, wireless IEEE 1394 (Firewire), and even wireless DVI, which is the digital display interface used to connect high-end monitors. Essentially, it is a way of eliminating most of the cables under the desk.

However, there are potential drawbacks for non-US users. It has not yet been licensed for use in the UK.

"It has been allowed by the FCC but not yet cleared for other countries," said Joyce Putscher, an analyst at communications industry research firm In-Stat. There seems to be some progress being made in the UK and there are a lot of things going on right now in Europe, Asian countries, Canada, and so on. But that doesn't happen overnight."

In January 2005 the UK government indicated it would support the more widespread use of ultra wideband.

Halksworth is positive about the coming together of Bluetooth and ultra wideband, saying that the two technologies are complementary. Bluetooth has solved the problem of wireless interoperability, getting different devices to talk to one another, he said. Instead of repeating all that work, ultra wideband can piggyback onto Bluetooth, offering data transfer speeds hundreds of times faster than traditional Bluetooth links.

Not everyone is convinced, however. "It is a blatantly political move," warned Heile. "They are looking at a way of cashing in on the ultra wideband cachet. Sprinkling it through Powerpoint presentations is a good way to get venture capitalists interested again."

Is there a danger that by shackling itself to ultra wideband, Bluetooth could end up relegating itself to little more than a handshaking technology?

"Yes, but if so there will be a lot of automobile companies that are very annoyed," said Heile. Car companies such as DaimlerChrysler have already embraced Bluetooth for hands-free phone calls.

What does all this mean to the average IT director? If ultra wideband takes off in the UK, it could mean an end to messy cabling, which would be a big boon to many offices. Pan technology also offers some benefits to mobile workers on the road.

But perhaps one of the most attractive propositions for corporates is Zigbee. Heile is also chair man of the Zigbee Alliance, an organisation that promotes the short-range radio standard, which has some unique features. Unlike other technologies, Zigbee focuses heavily on low power consumption, leading to extremely long battery life - years instead of hours. It is designed to support tens of thousands of nodes.

Zigbee is being promoted largely for building automation. The protocol enables the creation of mesh networks, in which any node can talk to any other node within range and route data through it - the way the internet works.

Having a Zigbee chip in lightbulbs placed at 30ft intervals, for example, would enable you to "flood network" a building, and if one or two nodes failed, the network would still operate. It would not be used for corporate Lan traffic because data speeds are too low but it could be used for building management information. Put Zigbee radio in a corporate ID badge, and you suddenly have a security network that knows where everyone is, for example.

According to Venkat Bahl, vice-president of marketing for Zigbee component manufacturer Ember and vice-chair of the Zigbee Alliance, Zigbee could benefit IT departments in other ways. For example, if one area of the building received less sunlight than another, light sensors attached to Zigbee sensors could dynamically adjust light levels, creating a better working environment and saving energy.

As the cost of Zigbee units falls from about £3 down to a more reasonable level, building automation will become more attractive. Zigbee could also be used for vertical applications in the field. A Zigbee-enabled piece of monitoring equipment, for example, could be read from a passing vehicle without having to be physically inspected, saving time for field engineers.

Such things may not be classified as Pans, strictly speaking, but Heile said he rues the day when he invented the term. "I regret that now because what started as a Pan space grew into an area that is sometimes personal and sometimes not."

Pans may develop into something that is not as personal as people once expected, but the benefits could be felt on both a corporate and an individual level, if the concept lives up to its ambitions the second time around, and if it can escape being typecast into a limited set of applications as Bluetooth has.


Standards bodies move towards unity       

Bluetooth can deliver data speeds of a few megabits per second in a range of 10m. It is primarily used in mobile phones and wireless headsets. 

Ultra wide broadband, also known as IEEE 802.15.3a, creates short-range, high bandwidth wireless connections. Capacity ranges between several hundred megabits per second and 2gbps within a range of 4m. It is primarily designed to connect consumer devices and deliver wireless streaming video services. 

The WiMedia Alliance represents a combination of WiMedia with the Multiband OFDM Alliance SIG - two leading organisations creating ultra wideband industry specifications and certification programs for consumer electronics, mobile and PC applications.  

A rival organisation, the UWB Forum, is dedicated to ensuring that standards-based ultra wideband products from multiple suppliers are truly interoperable. It also facilitates the regulatory approval process for ultra-wideband systems.

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