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A comment on Explained from scratch: private information retrieval and homomorphic encryption. Parent comment

Re:Explained from scratch: private information retrieval and... by onetimeusename on Monday September 26, 2022 @09:23PM (#32990682)
How does verification of data encrypted this way work say by the party that made the query? Like what is to verify that the cipher text was not tampered with? Can this be done?
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Re:Explained from scratch: private information retrieval and... by blintz on Monday September 26, 2022 @09:55PM (#32990840)
There's no single way to do this kind of verification. Different applications will have different 'roots of trust' for the authenticity of database data.

For example, for Wikipedia, we could imagine the Wikipedia site serving the PIR themselves (they are already the entity you trust to decide what is on Wikipedia). A third party wishing to mirror Wikipedia over PIR might try to get some kind of digital signature over the contents of each article from Wikipedia or another trusted source.

For blockchain queries, there are more technical solutions. For Bitcoin, for example, we could include a Merkle tree proof-of-inclusion for the transaction (a la BIP 37).

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