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Questions tagged [anonymity]

Anonymity describes the state of being unknown or unacknowledged.

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Cryptographic Challenge: How to Say Something Confidentially to Snowden?

The Snowden situation raises an intereting cryptograpic problem. At present, how can something be sent confidentially to Snowden? Claim: I have no particular political orientation. The above question is merely a cryptographic challenge. The meta…
Pigmann
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Anonymous trust/reputation system

Suppose there are 3 persons, Alice, Bob and Peter. They are identified by their pseudonyms (public RSA keys). Alice has a key Alice, Bob has Bob-Work and Bob-Friends. Peter has Peter. Peter knows Alice. Alice expresses trust to Bob-Work. Peter knows…
wizzard0
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Providing tokens for anonymous survey

I want to conduct an anonymous Internet survey (e.g. “What’s your favorite fruit?” with a multiple choice answer) among a given set of people. Double answers by the same participant are not allowed. I’m looking for a method to conduct this survey…
Alfe
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What is the best way to pseudonymise IP addresses while retaining the ability to identify those that share a subnet?

Background: I'm developing an app that is based around registered users voting on stuff, and I want to create a heuristic that involves IP addresses as one way to flag accounts for further investigation of potential multiple account+vote abuse. In…
Inkling
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Approach towards anonymous e-voting

I want to implement an internet-based e-voting system. Voters shall be able to cast their vote for one out of n possible candidates. Each candidate has his own ballot-box kept by and at a trustworthy third party. This third party is absolutely…
Thomas Lieven
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Private Messaging

Suppose Alice and Bob wants to send messages through Sue without revealing to Eve that the exchange took place. Slightly more formally, I don't want Eve to have any advantage telling if Alice is sending spam to random recipients, or if Alice is…
Henrick Hellström
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Current Status of mixnets for voting

I am currently doing some research on universally verifiable mixnets, but it seems to me that there are too few papers about them after 2006 or so and most of them come from the team of Douglas Winkstrom. Is this correct? Can anybody point me to…
Panagiotis Grontas
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What are the actual anonymity features of ZCash?

I have looked at their FAQ but I didn't find the answer to this. Having looked at their whitepaper, it seems to me that the main feature of ZCash is that you can't trace where the money came from, because of zero-knowledge proofs. My question is,…
Gregory Magarshak
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Can you identify the public key used to encrypt something?

If I encrypt a string with a public key, does the encrypted ciphertext reveal the public key I used to encrypt it? Basically, I don't want anyone to know who the ciphertext is addressed to. I'm thinking about RSA, but also interested in DSA. The…
Xeoncross
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What crypto system allows for 3 parties: Party 1 who makes an assertion, Party 2 mutates the assertion, Party 3 validates it

I'm looking for the cryptographic equivalent of a Drivers license where the issuer can be verified, the issuer doesn't need to know who you showed the drivers license to, but also allows per-transaction privacy. I would use the standard PKI system,…
makerofthings7
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Is it possible to derive an Ed25519-public-key from an Ed25519-signature?

If you have an Ed25519-signature and the signed message, can you derive the corresponding public-key or is the signature anonymous (except if you already know the public-key of course)?
K. Biermann
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How CL-signature can act as positive & additive accumulator?

A paper (http://ieeexplore.ieee.org/abstract/document/7961987/) proposes a Braavos (adaptively sound dynamic positive accumulator). Braavos uses two other accumulators. One is adaptively sound positive additive accumulator $ACC_A$ and the other is…
takita
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Check if two anonymously signed messages have the same author

I need digital signature scheme with following rules: Signature is "anonymous" which means it doesn't expose author identity (See papers in this answer. Anonymous RSA version or Boneh-Boyen algorithm satisfy this clause). Author can create some…
marmalmad
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Alice answering Bob without knowing the question

I'm a student and I don't know how to solve the following problem : Alice is proposing a 10 questions list to Bob. Bob choose only 1 question and wants to know the answer without Alice knowing the question. Alice wants that Bob can only have 1…
Valentin Degrange
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State of the art techniques for Anonymous Authentication?

What are the state of the art techniques for Anonymous Authentication? What are the most popular ones? The problem domain I am considering is with respect to different users accessing cloud content; lets say watching movies in Netflix. I am looking…
Usernepee
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