Claudio Guarnieri's BLE ATLAS Demonstrates How Busy the Airwaves Are — an Issue for Contact Tracing

Streaming valid BLE contacts from a single sensor, Guarnieri's project demonstrates the difficulties in using the tech for contact tracing.

BLE ATLAS shows how congested the Bluetooth airwaves air. (📷: Claudio Guarnieri)

Security researcher Claudio Guarnieri has launched a website which publishes data from a Bluetooth Low Energy (BLE) sniffer in real-time — as a means of demonstrating how proposals to use BLE for contact-tracing people potentially exposed to the coronavirus may underestimate how congested the airwaves really are

Contact tracing is one of the key weapons in the fight against COVID-19: When a person has been diagnosed with the disease, all persons with whom they have had contact over the likely infectious period are contacted — either so they can be tested themselves or, in the absence of adequate testing facilities, so they can isolate themselves until symptoms show or the incubation period is over.

Asking a person to remember everyone they've seen over a two-week or longer period, though, is difficult — which is why companies are turning to technology to help. Accent Systems recently unveiled a Bluetooth Low Energy wristband which would automatically log all other wristbands it has seen; Apple and Google, meanwhile, are working on a combined project to integrate contact tracing technology into their respective smartphone platforms.

Guarnieri, however, believes that contact-tracing through Bluetooth and Bluetooth Low Energy may be tricker than anticipated — thanks to the sheer number of devices out there. To prove a point, he has launched BLE ATLAS: a website that offers a life view of all the BLE devices in sight of his sniffing sensor.

"This is a broadcast from a sensor that I am running," Guarnieri told Motherboard in a brief interview on the project. "It's sort of a livestream of where I am. I imagine many like me are finding themselves wanting to understand better this new old space we are asked to be tracked on."

"BLE ATLAS is a project to explore BLE beacons, by visualising in real-time ADV_NONCONN_IND beacons received by a Bluetooth sensor I am running," Guarnieri further explains in a write-up of the system. "This project is both an experiment as well as a digital work. It attempts to analyze Bluetooth surroundings, expose the unexpected amount of transmissions, and analyse inconsistencies in the light of the upcoming surge in use.

"At the same time, BLE ATLAS attempts to subvert the supposed locality of these transmissions, and betrays their expected ephemerality by wilfully live-streaming them to the Internet. The system does not store any data, and it does not visualize any identifiable information or content of the transmissions."

More information is available on Guarnieri's website and the BLE ATLAS site itself — though the latter does not broadcast 24/7, for reasons of power draw and bandwidth usage.

Gareth Halfacree
Freelance journalist, technical author, hacker, tinkerer, erstwhile sysadmin. For hire: freelance@halfacree.co.uk.
Latest articles
Sponsored articles
Related articles
Latest articles
Read more
Related articles