The latest version of the wireless Bluetooth standard may not seem like a big deal, but it sets the scene for an ultra-fast version due next year, and readies Bluetooth for a coming contest against wireless USB, according to the Bluetooth SIG.

Two years ago, Bluetooth 2.0 arrived, boosting Bluetooth speed from 700 kbit/s to 3 Mbit/s. "That was rather dramatic," says Anders Edlund, marketing director for the Bluetooth SIG, "and a major improvement for people working with computers. But when it comes to volumes, version 2.1 might have a bigger impact."

The biggest change in the recently announced Bluetooth 2.1 is easier pairing, according to Edlund. There's also some new approaches to secure pairing, and a reduction in the power demands, all of which are aimed at getting more people to use the Bluetooth that's in their handsets - before the competition arrives.

Goodbye to pairing keys

Pairing Bluetooth devices involves entering a key code - not something that would scare Techworld readers, but it has held the protocol back amongst the wider world, says Edlund. "You do it once and forget it, but even so it is not exactly intuitive. You have to read the manual, and perform several steps.

There are two improved pairing methods. One uses Near Field Communications (NFC), the same technology used in proximity payment cards, which is increasingly being built into phones by vendors such as Nokia. "To pair a phone and a headset, you just need to touch them and press the yes key," says Edlund. "That is a dramatic improvement in the user experience, and more secure." Eliminating the PIN code prevents a man-in-the-middle attack.

The other new method, is not as easy as NFC, but uses Bluetooth alone. "You need to initiate pairing on the mobile, in the Bluetooth menu. There is a quicker search than in the past, and pairing just means pressing the button on a Bluetooth 2.1 headset."
The faster search involves a "limited enquiry access code". It also introduces a "find me" tag sent by a device that is waiting to pair - these tags are prioritised in the list of devices found.

More power to Bluetooth

The lower power requirement of Bluetooth is also more important than you might think, says Edlund. Keyboards and mice using the new version should last fives times longer on a set of batteries, taking typical performance form a month to nearly half a year, though "it depends how much you use keyboard," he adds.

Products using the new version will come in gradually, starting a few months from now, much as happened with Bluetooth 2.0: "It could be close to a year before you see very many of them."

The handset manufacturers aren't going to make a big song-and-dance about the new Bluetooth, says Edlund, although they put it together: "Bluetooth isn't a major feature of mobile phones. Handset makers boast about cameras and things, but rarely talk widely about the version of Bluetooth. That is good - people shouldn't need to worry too much about different versions of Bluetooth."

Ready for ultrawideband?

Among the profiles for Bluetooth, there will soon be one for streaming video. But that will wait till Bluetooth version 3, due early next year, which will be based on ultrawideband, a short-range high-speed network technology, and have speeds somewhere around 400 Mbit/s.

"That work is going according to plan," says Edlund. Ultrawideband is also getting good backing from the authorities, including the EU. The EU has announced a frequency allocation, using frequencies above 6GHz, which is very much in line with what the Bluetooth SIG has been doing."

A struggle with wireless USB?

But when Bluetooth 3 arrives, it will not be alone. A wireless version of USB, based on the same ultrawideband technology, will also be available. "I personally don't think there will be a battle," says Edlund. "In many devices, you will see wireless USB and Bluetooth, using the same radio, depending on what software is running," he says.

Bluetooth is very strong in ad hoc scenarios, where a device transfers data quickly and then switches off, but is less oriented to ad hoc use, he says. In fact, the situations where USB is currently used rarely demand wireless. Many USB devices are heavy and stationary, such as printers, so wireless connections are not necessary, and others such as MP3 players are usually charged over USB. They still need a wire for power, so why use wireless USB?

"There are five or ten times as many USB devices, but I don't think all that many of those will go to wireless," says Edlund. "USB has a lot to learn about wireless." It will be a while before wireless USB establishes mechanisms for ad hoc pairing, and the profiles for particular applications that the ad hoc mode requires.

High-speed Bluetooth starts with an advantage that it is entering a world where things are already wireless. Within that world, high-speed Bluetooth will take a long while to come to higher volumes, but it may also take over new areas, such as wireless projectors, says Edlund.."That's an area where WiFi is not friendly enough, and wireless USB would make sense. But that scenario is better for BT, because it is ad hoc."