Who Am I? Secure Identity Registration on Distributed Ledgers

  • Sarah AzouviEmail author
  • Mustafa Al-Bassam
  • Sarah Meiklejohn
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10436)


Bitcoin is a decentralized cryptocurrency that uses a ledger (or “blockchain”) to keep track of the transactions made between its users. Because it is a fully decentralized system and anyone can join, every transaction is by necessity public. Thus, to preserve some semblance of privacy, users in the system are represented not by their real-world identities but by pseudonyms. While pseudonyms are acceptable for a standalone cryptocurrency, the emergence of other potential blockchain-based applications — e.g., using them to administer benefits and pensions — poses a need to associate certain attributes with the users of the system. In this paper, we address the question of how to register identities and attributes in a system built on globally visible ledgers. We propose a variety of possible solutions and in each case, we analyze the tradeoff our solution provides between privacy (ensuring that no one can associate the user’s real-world identity with the pseudonym or other attributes they use on the ledger), usability (ensuring that verification of their attributes poses the lowest possible burden to users), and integrity (ensuring that no one can impersonate a user). We also present an implementation of one of our solution using Ethereum.


Distributed Ledger Blockchain Bitcoin Real-world Identity Smart Contracts 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This project was supported in part by EPSRC Grant EP/N028104/1.


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Sarah Azouvi
    • 1
    Email author
  • Mustafa Al-Bassam
    • 1
  • Sarah Meiklejohn
    • 1
  1. 1.University College LondonLondonUK

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