User-Generated Pseudonyms Through Merkle Trees

Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 12703)


A pseudonymisation technique based on Merkle trees is described in this paper. More precisely, by exploiting inherent properties of the Merkle trees as cryptographic accumulators, we illustrate how user-generated pseudonyms can be constructed, without the need of a third party. Each such pseudonym, which depends on several user’s identifiers, suffices to hide these original identifiers, whilst the unlinkability property between any two different pseudonyms for the same user is retained; at the same time, this pseudonymisation scheme allows the pseudonym owner to easily prove that she owns a pseudonym within a specific context, without revealing information on her original identifiers. Compared to other user-generated pseudonymisation techniques which utilize public key encryption algorithms, the new approach inherits the security properties of a Merkle tree, thus achieving post-quantum security.


Data minimisation General data protection regulation Merkle trees Personal data Pseudonymisation 



The authors would like to thank the anonymous reviewers for their very useful comments which helped to improve the paper.


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Authors and Affiliations

  1. 1.School of Pure and Applied SciencesOpen University of CyprusLatsiaCyprus
  2. 2.Hellenic Data Protection AuthorityAthensGreece
  3. 3.Department of Informatics and TelecommunicationsUniversity of PeloponneseTripolisGreece

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