Ramesh Raskar: Hello everyone.
I'm Ramesh Raskar, associate professor at MIT media lab and let's talk about a question
that's coming up quite a bit, about whether you should use Bluetooth or GPS for contact
tracing.
And how can we create privacy aware contact tracing that's great for public health, but
also restarting the economy.
As you know digital contact tracing, is about creating a solution that would notify a citizen
if they have crossed path, and send them an alert that provides location of where the
contact may have occurred, and use GPS and Bluetooth technologies in smart phones.
And at MIT we are proposing two solutions, safe paths and safe places for a comprehensive
public health digital ecosystem.
Now privacy is not just about, an individual's privacy, it's also about consent and regulation,
are trade secrets between different organizations and even national security.
As in the end, why should even healthy people participate?
What's the incentive for them?
Ramesh Raskar: So there are many reasons why digital contact
racing is not easy to deploy.
The approach we're taking for safe paths is to create a series of solutions.
The first solution is simply a location logger that logs your location, and then compares
with any publicly available data of infection cases.
In version two, the same logs, this private diary, can be compared with more detail information,
of infected individuals, infected cases, from public health.
And version three which is not out yet.
We want to reduce the burden on health officials using self reporting, self authentication,
as well as computational methods.
And now welcome to, try out the beta version for the Safe Paths mobile app that's already
in the App Store and Mobile Store.
And we also have a very large open source community, available on GitHub.
So, if you're a governmental organization or health authority, you can download our
code and get running with your own app in a matter of hours.
Ramesh Raskar: And for public health we also have a web tool
called safe places that allows them to do faster and more accurate interview, patient
interviews so that they can import, history from last several days, or redact, personally
identifiable information and perform anonymization, aggregation and in the future, even encryption
of that trail.
And just go for an all view, of how we see the safe paths, safe places ecosystem.
In terms of technology, our goal is to support all kinds of proximity technologies such as
GPS and Bluetooth, and Apple, Google APIs as well as our friends at MIT, the MIT [pract
00:02:49] protocol, WiFi and others.
And the Safe Paths app right now is about exposure notification, and access resources.
But very soon it will also have, personalized guidance and symptom tracking and even downstream
applications like quarantine and immunity and verifications.
At the same time, we also want to support public health, by allowing them to directly
call the infected person, create heat maps and spread analysis and achieve all of this,
while preserving the privacy of an individual.
Ramesh Raskar: So this is the key idea, we're in Safe Paths,
achieve all the goals of public health, contact tracing challenges, while maintaining privacy
for the citizens.
The exciting news is that Google and Apple have announced their proximity API.
And the way it works, based on Bluetooth is that two phones, let's say the healthy person
and the infected person's phone, exchange their keys by whispering over Bluetooth and
only the infected person uploads their keys to the server and all the healthy individuals
can download the keys from the infected person and see if there's a match on... with aspect
to what they heard over the local Bluetooth channels.
That's just kind of, at a very high level overview of how this works.
So this is exciting because it will be available in majority of phones.
Ramesh Raskar: Now, if you...
The debate between should you use Bluetooth or GPS, let's get into that.
First of all, a proximately API on its own, does not create a contact tracing solution,
because contact tracing is about location and context.
And if you don't have location context, then it creates certain hazards.
So if you provide a solution where the citizen gets...
The only information the citizen gets, is you're exposed without a context, it can turn
to a lot of challenges.
First of all, the users will have a very low trust in the system, because they won't be
able to understand where the false positives and false negatives.
If they went in a grocery store, and that's where they had an encounter, but they didn't
know that the Bluetooth warning is coming because of their presence in the grocery store.
It'll be confusing because this individual might have been very careful when they went
to the grocery store wearing a mask, maintaining a social distance, so that alert will be meaningless.
Ramesh Raskar: On the other hand, they went to a wedding
and at that wedding, they were not as careful.
They would like to know, if the infected person was at that wedding.
And just lack of agency, the lack of understanding and the confusion, can lead to irrational
behavior, it can lead to risky behavior, of all people ignoring it altogether.
Another challenge with a system that only indicates you were exposed, is that public
health need to actually go to interview this exposed individuals, then have location and
context to create the heat maps and also perform the spread analysis.
So, if you don't have this context, it can also lead to some serious societal challenges.
And we have already seen that, this unfortunate incidences in certain countries.
So if the individuals don't a context, they're going to blame, for the exposure onto people,
they like to blame.
Often, minorities in a community, and they can say, "Because of this particular group
of people, we're getting a lot of infections, without knowing the context."
Ramesh Raskar: And then, our zealous enforcement authorities
can also, really start targeting, these groups.
So that remains a challenge.
And, if you start putting neighbor against neighbor, it can even lead to civil unrest,
which has happened in certain parts of the world because of such digital solutions.
And, if you're from public health, you also know that public health requires not just
contact tracing, but they also want to do quarantine verification, in order to manage
the population that is staying home because, of self isolation, in order to food or medicine,
health verification, immunity passport.
So public health solution requires much more than proximity and even more than contact
tracing.
So let's see how we can use Bluetooth and GPS.
If you use Bluetooth, the good news is that, it's not the best proximity detectors.
It can measure approximately between two phones down to feet or even meters, accurately.
Ramesh Raskar: And you can get pretty good privacy as long
as the server where you place those Bluetooth keys, and the apps that can access that server
is very tightly controlled.
So Apple and Google are promising that they will tightly control this apps and the server.
Nevertheless, the challenge is that any Bluetooth signal you emit from a phone can be snooped.
So the challenges here is that we have to believe that Apple and Google are been involved,
which I believe or, a protocol like the MIT pact, it will become the standard because
I think it's even better.
The challenge of it, Bluetooth again, is that, adoption can have a significant impact on
effectiveness.
So even at 12% adoption, in a country like Singapore, it will only capture 1.44% of encounters,
because the square of 12 is 1.44, in percentage.
Another challenge with Bluetooth is inclusivity.
Ramesh Raskar: If users don't have smart phones, or they
don't opt in, they will get no information whatsoever.
And false positives and false negatives can again, reduce the trust in the system.
One challenge with Bluetooth is that, since it's emitting a Bluetooth chirp very regularly,
it can be snooped by a third party app, that maybe used by hundreds of millions of people.
And this third party app company can gather all the data and create a global surveillance.
Another challenge is that, the keys cannot be in public domain, they have to be tightly
controlled.
So right now Apple and Google are large companies that are hosting it, but this is creating
some friction.
So for example, France, has claimed that France should be allowed to keep those keys, otherwise
it's going to stifle the innovation in those countries.
Ramesh Raskar: What about GPS?
GPS has its own benefits and challenges.
On one hand, GPS provides great privacy because absolutely nothing leaves the phone of a healthy
person.
And all the computation can be done on the phone.
So it's the best privacy you can ever imagine as long as you don't have to upload any data.
It's available on most phones, easy to implement and, adoption versus effectiveness, is also
linear.
If 12% of the population is using a GPS based solution, then 20% of the infected sites,
will be released to the public.
And it's also very inclusive because even if individuals don't use a smartphone or even
a phone, this 12% of the hotspot, can be disseminated to the population, the town, through TV channels
or SMS or any simple mechanisms.
So, it's very inclusive in that sense.
The challenge with GPS is that it's not as accurate as Bluetooth.
So that can lead to its own false positives and false negatives.
Ramesh Raskar: Another challenge is that for the infected
person, to make sure that the manual contact racing experts are doing the right job into
moving the personally identifiable information.
And which means they need some training.
In case of Safe Paths, we're very fortunate that, [inaudible 00:10:10], is providing this
training, to this, health professionals, nevertheless, it remains, an open problem.
And although we are not implementing it, in the current version, if full flush encryption,
[inaudible 00:10:21] for GPS requires two servers rather than one server.
That will come in the future.
The benefit of the location and context however, does improve the trust in the system because,
a public health official can talk to the user and say, "Hey, looks like you had an encounter.
Were you at a grocery store or were you at a wedding?"
And the user can explain verbally, "Hey, I was in the grocery store but, I was wearing
a mask, so I don't think I should worry about it, but if I was at the wedding I should probably
self quarantine for 14 days."
Ramesh Raskar: And for public health, this location and context
again becomes very easy to interview, individuals even on the phone and for heat maps and spread
analysis.
The obvious answer here is why not combine both, Bluetooth as well as proximity and we
get the best of the two.
We can use Bluetooth for proximately detection.
We can use GPS, which stays completely on the phone and never uploads any data to provide
any geo-fencing based solutions.
So, this is great, right?
Because, Bluetooth can provide more accuracy in terms of proximity, you'll be supported
by Apple and Google or the MIT pact protocol, and GPS can stay on the phone.
At the same time, the GPS can be used as a backup in case Bluetooth is unreliable, or
the user has opted out.
Because as I've said before, GPS is the most private way to log your own personal data.
Ramesh Raskar: So, if that's that's made available, then
the GPS log can happen on the phone or the calculations happen on the phone, and the
user can create geo-fences saying, "Hey, if I'm at home or any other sensitive place,
I don't want to record anything at all."
An infected user, public health officials, then they call infected user, they can use
this personal logs on their phone and that can help them jog their memory.
So this kind of context, location context, can eliminate false positives and improve
the location.
So we strongly recommend a solution that combines Bluetooth and GPS in Safe Paths.
Other factors if you're a government or health entity to consider, is are solutions privacy
first, because not just about kind of freedom of the citizens, but is also important for
adoption.
Is it open source, so that it's not locked into any particular vendor?
Because if it's not open source, then how...
If you want to expand the functionality, you don't want to be dependent on a particular
vendor.
Ramesh Raskar: Is it interoperable if the citizen goes from
one country to another country or one state to another country?
Are the solutions going to talk to each other?
Does it support multiple languages?
Does it support non smartphone users, through TV and SMS and other channels?
And does it actually create a ecosystem for public health so that we can, use this context
for as I said, for hotspots and spread analysis and so on?
And finally, is it modular or is it yet another solution you have to use that's going to displace,
the already public health IT, public health IT systems, you already have?
So this are [inaudible 00:13:31] considerations we have taken for safe paths and safe places.
So, we are very delighted to have a wonderful alliance, and lot of our work, is shaped by
mentorship from WHO, and HHS and CDC and Mayo clinic and so on.
Ramesh Raskar: And we also have a nonprofit parts check that's
working with [inaudible 00:13:50], to really deploy the solutions in more than 40 jurisdictions.
I bear we have ongoing conversation.
And because we have a very large GitHub, very large open source community, these solutions
are improving by the hour and by the day.
So you can think of Safe Paths as having three pillars.
One, is we have the technology which is the flagship mobile app and a web tool for health
professionals, but we also have an opensource score base.
So anybody in the world can take our code base and within a couple of days have your
own app, up and running.
Or, if you're a company that wants to simply use an APIs from Safe Paths, you can do it
as well.
And our team continues to publish more [inaudible 00:14:34] terms, more techniques, completely
in the public domain.
Ramesh Raskar: And because we want to allow every app, every
software solution to be interoperable, we're also creating an interoperable backbone.
So it's not about competition and pushing the Safe Path mobile app, but we want to make
it compatible with any solution that's out there.
Where there's for-profit, nonprofit, where there's open source, or close source, we want
to support all of them.
Safe Paths also has a think tank pillar, that's working on privacy guidelines and ethics guidelines
and interoperable standards, and we publish documents on landscape analysis comparing
various apps, comparing various solutions, and so on.
And on the implementation side, we have a public roll outs, we have training material,
we have a venture support, if you're a organization who's providing solutions, and we also have
corporate engagements.
So check our website for that.
So to conclude, of course to overcome this public health and economic challenge, we need
to have a choreography by the government and large businesses.
At the same time, because of privacy and regulation and consent and ethics, we had to let the
citizens and communities, coordinate amongst themselves.
And for that, in order to create privacy preserving solutions.
Thank you.