Bluetooth tracing forms the basis of contact tracing, and that is the reason Google and Apple have decided to come together to develop this mechanism, but GPS is also essential.
The controversy surrounding most contact tracing apps is that they give unfettered access to the government, and governments can track users location using the app. The concerns are well-founded, and most governments have done well to ensure users that their data is safe. But when Apple and Google, last month, announced that they would be using only Bluetooth and not location data, it spurred a debate on how important location is to contact tracing.
How do most apps do contact tracing?
For most apps, contact tracing is done using two data sets. The Bluetooth chip has a receiver and a transmitter, it pings other phones when it comes in contact with another chip, and the phone registers this ping making a record of it. Once a person is detected to be Covid positive, the government can decode the pings to inform whosoever has come in contact with the infected person. Plus, it can track location data, which these days is collated using a technology called AGPS to trace the person’s whereabouts over the last 14-days. It can then inform users to be cautious about these places. As Coronavirus is a fomite infection, this process also assumes importance.
What is AGPS?
AGPS or Assisted GPS is the technology that uses cellphone triangulation and GPS chip to determine the location of a person. The signal triangulation helps in real-time updates, whereas GPS, which is usually slower, lend accuracy to the system.
So, can contact tracing be done using Bluetooth and without GPS data?
Bluetooth tracing forms the basis of contact tracing, and that is the reason Google and Apple have decided to come together to develop this mechanism, but GPS is also essential. Mobile signal triangulation can help the government determine a person’s location, but the mechanism is far from precise. It is instrumental in places where there are a lot many towers, but not so much in areas where there are less. The whole concept is based on your distance from the tower and the estimating where you may be. If governments do follow this approach, their target area will increase because of imprecise location.
Besides, another reason AGPS or GPS is important is because contact tracing is just one part of the function these apps fulfil. They also need to alert users whether they are in a high-risk zone. The only way they can do this is by obtaining a user’s information. This way, a user can be informed whether she is in a high-risk zone and what precautions she needs to take. It also alerts her to new cases, so that is mindful of her surroundings.