Blockchain access privacy: Challenges and directions

Ryan Henry, Amir Herzberg, Aniket Kate

Research output: Contribution to journalArticlepeer-review

199 Scopus citations


Privacy, facilitated by a confluence of cryptography and decentralization, is one of the primary motivations for the adoption of cryptocurrencies like Bitcoin. Alas, Bitcoins privacy promise has proven illusory, and despite growing interest in privacy-centric blockchains, most blockchain users remain susceptible to privacy attacks that exploit network-layer information and access patterns that leak as users interact with blockchains. Understanding if and how blockchain-based applications can provide strong privacy guarantees is a matter of increasing urgency. Many researchers advocate using anonymous communications networks, such as Tor, to ensure access privacy. We challenge this approach, showing the need for mechanisms through which non-anonymous users can (i) publish transactions that cannot be linked to their network addresses or to their other transactions, and (ii) fetch details of specific transactions without revealing which transactions they seek. We hope this article inspires blockchain researchers to think beyond Tor and tackle these important access privacy problems head-on.

Original languageEnglish
Article number8425613
Pages (from-to)38-45
Number of pages8
JournalIEEE Security and Privacy
Issue number4
StatePublished - 1 Jul 2018
Externally publishedYes

Bibliographical note

Publisher Copyright:
© 2003-2012 IEEE.


This material is based on work supported by the National Science Foundation under grants 1718595 and 1719196, and by United States-Israel Binational Science Foundation (BSF) under grant 2016718.

FundersFunder number
National Science Foundation1719196, 1718595
Bloom's Syndrome Foundation2016718
United States-Israel Binational Science Foundation


    • PIR
    • Tor
    • anonymity
    • bitcoin
    • blockchain
    • blockchain security and privacy
    • privacy
    • private information retrieval
    • security


    Dive into the research topics of 'Blockchain access privacy: Challenges and directions'. Together they form a unique fingerprint.

    Cite this