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Oh cool, the Bluetooth 5.1 specification is out. Nice. *control-F* master-slave... 2,000 results

Can't let go of that old terminology we see. Plus, it now tells you where a nearby device is located

Version 5.1 of the Bluetooth wireless networking specification debuted recently, bringing with it the ability to identify the direction of a transmitting Bluetooth device from a receiving antenna – and divisive technical jargon.

Directional location finding has the potential to improve Bluetooth location-based services and make new services possible. There are, of course, other technologies that can be used for positioning, such as Wi-Fi, GPS, RFID and NFC. But Bluetooth Low Energy has advantages where bandwidth requirements and distances are small.

In a blog post, Dave Hollander, director of marketing for the Bluetooth Special Interest Group, says the spec allows for centimetre-level accuracy in pinpointing the location of a transmitting gadget.

This makes the technology suitable for applications like finding items with Bluetooth-enabled tags, point-of-interest information displays in museums, precise asset tracking in industrial settings and better indoor wayfinding, among others.

The authors of the revised spec, however, missed the memo that master-slave terminology is inconsistent with inclusive development communities and has been purged from various open source projects. The almost 3,000-page spec is littered with the terms – each appears about 2,000 times.

The Register called the Bluetooth SIG to ask about this and was referred to a media handler who wasn't immediately available.

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Cultural cluelessness aside, this latest flavor of Bluetooth adds support for Angle of Arrival (AoA) and Angle of Departure (AoD) methods, which can be used to allow one Bluetooth radio to find the direction of another such radio.

Previous versions of Bluetooth have allowed real-time location services for several years through Bluetooth beacons, which could provide rough estimates of the distance between objects through signal strength measurements. The addition of AoA and AoD will make distance measurement much more precise, in addition to providing an accurate direction angle.

John Leonard, product marketing manager at Nordic Semiconductor, says the absolute real-time positioning of objects in 3D space represents a significant addition to Bluetooth Low Energy.

"We believe it can have a similar impact for indoor situations as GPS did for outdoor positioning," he explains in a blog post. "Where GPS has fundamentally changed the world of traveling and tracking on the macro scale for cars, people and objects, Bluetooth direction finding can make a similar impact on the micro scale inside buildings and properties."

He cautions, however that crowded environments with obstacles, which can affect signal phase and strength, raise the risk of errors in direction finding calculations. Thus he recommends testing applications that implement direction finding before deployment.

Security also remains an ongoing concern for IoT devices implementing Bluetooth tech.

"Bluetooth is only going to continue to become more refined with more powerful connectivity capabilities," said Nadir Izrael, CTO and cofounder of security biz Armis, in an email to The Register.

"We know of vulnerabilities in Bluetooth implementation level, and in the BLE chip. But malicious hackers are finding novel ways to exploit Bluetooth due to the rise of IoT - exploits that are currently sliding under the radar of existing security solutions." ®

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