Well they don’t. I don’t want to justify the opt-in by default but, again (cf my reply history) here they are precisely trying NOT to send anything usable to their own server. They are sending data that can’t be used by anything else but your phone. That’s the entire point of homomorphic encryption, even the server they are sent to do NOT see it as the original data. They can only do some kind of computations to it and they can’t “revert” back to the original.
If they don’t look at my data, they don’t even have to encrypt it.
If they don’t try to look at my data, they don’t need to wonder whether they should ask my permission.
I don’t want Apple or anybody else looking at my data, for any reason, is my point.
Yet I’ll still try to clarify the technical aspect because I find that genuinely interesting and actually positive. The point of homomorphic encryption is that they are NOT looking at your data. They are not encrypting data to decrypt them. An analogy would be that :
we are a dozen of friends around a table,
we each have 5 cards hidden from others,
we photocopy 1 card in secret
we shred the copied card, remove half of it, put it in a cup and write a random long number on that cup
we place that cup in a covered bowl
one of us randomly picked gets to pick a cup, count how many red shards are in it, write it back in the cup and writes adds the number to the total written on the bowl, we repeat that process until all cups are written on only once
once that’s done we each pick back our up without showing it to the others
Thanks to that process we know both something about our card (the number of red shards) and all other cards (total number of red shards on the bowl) without having actually revealed what our card is. We have done so without sharing our data (the uncut original card) and it’s not possible to know its content, even if somebody were to take all cups.
So… that’s roughly how homomorphic encryption works. It’s honestly fascinating and important IMHO, the same way that cryptography and its foundation, e.g. one way functions or computational complexity more broadly, are basically the basis for privacy online today.
You don’t have to agree with how Apple implemented but I’d argue understanding how it works and when it can be used is important.
Let me know if it makes sense, it’s the first time I tried to make an analogy for it.
PS: if someone working on HE has a better analogy or spot incorrect parts, please do share.
Well they don’t. I don’t want to justify the opt-in by default but, again (cf my reply history) here they are precisely trying NOT to send anything usable to their own server. They are sending data that can’t be used by anything else but your phone. That’s the entire point of homomorphic encryption, even the server they are sent to do NOT see it as the original data. They can only do some kind of computations to it and they can’t “revert” back to the original.
If they don’t look at my data, they don’t even have to encrypt it.
If they don’t try to look at my data, they don’t need to wonder whether they should ask my permission.
I don’t want Apple or anybody else looking at my data, for any reason, is my point.
I agree on permission.
Yet I’ll still try to clarify the technical aspect because I find that genuinely interesting and actually positive. The point of homomorphic encryption is that they are NOT looking at your data. They are not encrypting data to decrypt them. An analogy would be that :
Thanks to that process we know both something about our card (the number of red shards) and all other cards (total number of red shards on the bowl) without having actually revealed what our card is. We have done so without sharing our data (the uncut original card) and it’s not possible to know its content, even if somebody were to take all cups.
So… that’s roughly how homomorphic encryption works. It’s honestly fascinating and important IMHO, the same way that cryptography and its foundation, e.g. one way functions or computational complexity more broadly, are basically the basis for privacy online today.
You don’t have to agree with how Apple implemented but I’d argue understanding how it works and when it can be used is important.
Let me know if it makes sense, it’s the first time I tried to make an analogy for it.
PS: if someone working on HE has a better analogy or spot incorrect parts, please do share.