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What is Differential Privacy?

blog.cryptographyengineering.com

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Re: What is Differential Privacy?

#21

Post by nixy »

hfsbtnye wrote: post #16
forgotpwtomain wrote: post #7

Earlier quoted context omitted.

> I only wish that they would go ahead and put everything under a free software license, since they're in the business of selling hardware that's coincidentally bundled with their software. That's never going to happen. Apple sells a 'User Experience' not just hardware - having a complete and mostly closed product is an inevitable consequence of the former - and the number of Linux users that would buy a Macbook isn'…

In what way does changing the software license impede user experience? No other company would have the proverbial balls to straight up copy their software either.

Have you heard about a company called Xiaomi? They have the balls to straight up copy the industrial design of Apple, so pretty sure they would have no problem copying the software.

Re: What is Differential Privacy?

#22

Post by conradev »

frankmcsherry wrote: post #18
bo1024 wrote: post #14

I've read a couple articles and haven't seen any details about how they're going to apply DP (differential privacy). It's important to clearly distinguish what DP can and cannot do. DP is just a technique for taking a database and outputting some statistic or fact about it. The output has some noise added to it. The guarantee of DP is (roughly) that anyone looking at the output alone won't learn much about anyone in…

> The database still has to exist on Apple's servers. It doesn't, which is part of the reason Apple wants to do this. You can still do differential privacy without collecting all the data, you just get less accurate results. See page 232 in [1], re "The Local Model". [1]: http://www.cis.upenn.edu/~aaroth/Papers/privacybook.pdf Edit: the article even says this down when it talks about RAPPOR.

Even though the technique doesn't require collecting all of the data, Apple still does collect a huge well of data.

They store all iCloud sync material (backups, photos, contacts, calendars, mail, documents, etc.) without end to end encryption, and have all of the iMessage metadata.

Re: What is Differential Privacy?

#23

Post by [deleted] »

cyphar wrote: post #10
aub3bhat wrote: post #8

Earlier quoted context omitted.

Good luck selling that to doctors. People who are trained to cut open a patient aren't receptive to hypothetical harms and imaginary "budgets". Consider the fact that cause of death records are public. The usual perception of privacy by theory and security researchers and norms practiced in healthcare differ enormously.

The point of differential privacy is to allow for aggregate analysis, without destroying the privacy of outliers. Researchers deal with noise all the time, so is it so odd that a field of researchers believe that adding enough noise to data released with studies will allow for conclusive analysis without ruining privacy for individuals?

[deleted]

Re: What is Differential Privacy?

#24

Post by jon-wood »

xufi wrote: post #9
tjl wrote: post #6

Earlier quoted context omitted.

They talked a bit more about differential privacy in the State of the Union. Basically, they hash the data and add noise. By collecting data from a bunch of people that noise gets averaged out. They also limit the amount of samples (over a relatively short period of time) they can get from a single person so they won't be able to identify them.

Intersting. That's a smart way to collect data while not having too much noise flood in the dataset. I need to watch this State of the Union.

State of the Union is what the WWDC keynote used to be before it started being watched by press and the public. Much more technical detail, and information in the underlying frameworks rather than user visible features.

Re: What is Differential Privacy?

#25

Post by [deleted] »

bo1024 wrote: post #14

I've read a couple articles and haven't seen any details about how they're going to apply DP (differential privacy). It's important to clearly distinguish what DP can and cannot do. DP is just a technique for taking a database and outputting some statistic or fact about it. The output has some noise added to it. The guarantee of DP is (roughly) that anyone looking at the output alone won't learn much about anyone in…

[deleted]

Re: What is Differential Privacy?

#26

Post by Twisell »

conradev wrote: post #22
frankmcsherry wrote: post #18

Earlier quoted context omitted.

> The database still has to exist on Apple's servers. It doesn't, which is part of the reason Apple wants to do this. You can still do differential privacy without collecting all the data, you just get less accurate results. See page 232 in [1], re "The Local Model". [1]: http://www.cis.upenn.edu/~aaroth/Papers/privacybook.pdf Edit: the article even says this down when it talks about RAPPOR.

Even though the technique doesn't require collecting all of the data, Apple still does collect a huge well of data. They store all iCloud sync material (backups, photos, contacts, calendars, mail, documents, etc.) without end to end encryption, and have all of the iMessage metadata.

This is so wrong. The only thing that isn't user-encrypted so far is the iPhone backup on their server (Of course it is encrypted but Apple have the key to decrypt it as needed).

The official explanation so far is that if the user forgot the password a user-encrypted backup would just become some useless junk.

This is (officially) the sole remaining non user-encrypted personal data on apple server that authority can reclaim using a warrant.

However after San Bernardino FBI mess, Apple start considering to also encrypt iCloud backup.

So if you think you are right, proofs please...

Re: What is Differential Privacy?

#27

Post by guelo »

Apple backed themselves into a corner by marketing themselves as the super-privacy company in contrast to Google. The problem is that all the data collection lets you do some really useful stuff that benefits the user. So now they're spreading FUD while trying to pretend that they're not collecting the same type of data that Google does. Google has been using differential privacy for a while in different projects.

Re: What is Differential Privacy?

#28

Post by bo1024 »

frankmcsherry wrote: post #18
bo1024 wrote: post #14

I've read a couple articles and haven't seen any details about how they're going to apply DP (differential privacy). It's important to clearly distinguish what DP can and cannot do. DP is just a technique for taking a database and outputting some statistic or fact about it. The output has some noise added to it. The guarantee of DP is (roughly) that anyone looking at the output alone won't learn much about anyone in…

> The database still has to exist on Apple's servers. It doesn't, which is part of the reason Apple wants to do this. You can still do differential privacy without collecting all the data, you just get less accurate results. See page 232 in [1], re "The Local Model". [1]: http://www.cis.upenn.edu/~aaroth/Papers/privacybook.pdf Edit: the article even says this down when it talks about RAPPOR.

Hi Frank and thanks for responding; you're right of course.

If Apple really did implement some sort of randomized response (or more sophisticated variant), I think that would a real breakthrough for user privacy since they'd be giving up control of the data.

Re: What is Differential Privacy?

#29

Post by [deleted] »

nixy wrote: post #21
hfsbtnye wrote: post #16

Earlier quoted context omitted.

In what way does changing the software license impede user experience? No other company would have the proverbial balls to straight up copy their software either.

Have you heard about a company called Xiaomi? They have the balls to straight up copy the industrial design of Apple, so pretty sure they would have no problem copying the software.

[deleted]

Re: What is Differential Privacy?

#30

Post by [deleted] »

cyphar wrote: post #10
aub3bhat wrote: post #8

Earlier quoted context omitted.

Good luck selling that to doctors. People who are trained to cut open a patient aren't receptive to hypothetical harms and imaginary "budgets". Consider the fact that cause of death records are public. The usual perception of privacy by theory and security researchers and norms practiced in healthcare differ enormously.

The point of differential privacy is to allow for aggregate analysis, without destroying the privacy of outliers. Researchers deal with noise all the time, so is it so odd that a field of researchers believe that adding enough noise to data released with studies will allow for conclusive analysis without ruining privacy for individuals?

[deleted]
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