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Questions tagged [pir]

A PIR (Private Information Retrieval) protocol allows a user to retrieve an item from a server in possession of a database without revealing which item is retrieved.

A PIR (Private Information Retrieval) protocol allows a user to retrieve an item from a server in possession of a database without revealing which item is retrieved.

Private Information Retrieval is a weaker version of $1$-out-of-$n$ oblivious transfer, where it is also required that the user should not get information about other database items.

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Confusion on Private Information Retrieval by Keywords

PIR protocols retrieve an item from the database without the server knowing which item it is. But classic CPIR(Computational PIR) or IT-PIR (Information Theoretic PIR) protocols requires the user to know the location address of the object to be…
sashank
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ORAM over Third Party DB

Oblivious Ram (ORAM) is a cryptographic technique that is used for secure DB querying without leakage on the access patterns. There are several schemes for ORAM, amongst the most popular ones, there is Path ORAM. However, and as far as I understand…
DaWNFoRCe
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What is the difference between PIR and OT?

A private information retrieval (PIR) protocol is a protocol that allows a user to retrieve an item from a server in possession of a database without revealing which item is retrieved. An oblivious transfer (OT) protocol is a type of protocol in…
w.qi
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Secure "table-look-up" operation

I am thinking about this problem: The server has a two-column table $T=\{c_1,c_2\}$. A user has a query $q$ that is sent to server. The server find an item $x$ in the first column satisfying $x=q$ and return the item $y$ in the second column to the…
Paradox
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What are Practical Primitives based on Lattices, LWE and FHE?

Lattice-based cryptography is being used for several primitives and applications. I know there are newer works for PIR, PSI, ORAM that have seen tremendous improvements due to FHE. In some cases, FHE is the only tool that can be used for practical…
LWE-13
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Private Information Retrieval with a pre-prepared database

Informally, Private Information Retrieval (PIR) is a protocol between a user $U$ and a Server $S$, that meets the following conditions: $U$ obtains enough information about a database hosted by $S$, to decide which record $i$ in the database to…
Henrick Hellström
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Collusion resistant computing of same function by two servers

Is there a secure way of computing same hash function of replicated data by two servers. I mean that both servers host the same version of replicated data and they should output h(M) without colluding, i.e., both of them really compute the specified…
Reyhan
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Private Information Retrieval and Writing at the same time possible?

Are there any (possibly multiserver) private information retrieval (PIR) schemes that support private reads and writes (so called PIR Writing) at the same time, while having sublinear (in the database size) communication overhead? The most recent,…
Cryptonaut
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Private Information Retrieval——which framework is using effectively now？

I have read some PIR papers, but I find the related discuss of PIR framework was in 7 years ago. So could somebody tell me，what is the mainstream PIR method in industry now？
艾霖轩
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How can a client privately query a subset of a database?

I am trying to build a solution for the following problem and I think it is relevant to crypto: Party A has a set of indexes M, such as a group of people's ID; Party B has information of a larger group of people, and we name the set of this group as…
S. Luo
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How can we deploy information-theoretic private information retrieval in practice?

I recently came to know that there is a notion called "information-theoretic private information retrieval". The assumption is that multiple non-colluding servers have same data set and a client wants to retrieve a specific element (or multiple…
user9414424
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Database sharing in Private Information Retrieval (PIR)

Private information retrieval (PIR) protocols assume multiple parties have copies of a search database. How practical is this in real world? (In more details the 'practical' term is: Will Google be ready to allow other independent search tools copy…
Ano
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Will the non-colluding servers communicate in IT-PIR schemes ?

The current literature around Information Theoretic Private Information Retrieval (IT-PIR) schemes assume the existence of multiple copies of the database distributed across non-colluding servers. Much of the research seems to be around the servers…
sashank
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Privacy-Preserving relational databases: checking the existence of a record (or multiple records)

I would like to know if there exists a protocol which performs the following operation in a privacy-preserving fashion: User $U$ wants to know whether a record is stored in the database. The primary key of the record is an id which is known by the…
pAkY88
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Concrete attacks on Private Information Retrieval (PIR)

Private Information Retrieval (PIR) protocols have been studied for years. The following question only regards to the single server scenario. Assume there are $N$ items in total on the server side, according to the security definition, it seems that…
alexander
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