1. Ouroboros Crypsinous: Privacy-Preserving Proof-of-Stake 2019 Blockchains e-cash Oakland
    Thomas Kerber, Markulf Kohlweiss, Aggelos Kiayias and Vassilis Zikas
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    author = {T. Kerber and A. Kiayias and M. Kohlweiss and V. Zikas},
    booktitle = {2019 2019 IEEE Symposium on Security and Privacy (SP)},
    title = {Ouroboros Crypsinous: Privacy-Preserving Proof-of-Stake},
    year = {2019},
    volume = {},
    issn = {CFP19020-ART},
    pages = {},
    keywords = {privacy;proof-of-stake;zero-knowledge;universal-composability;adaptive-security;blockchain;distributed-ledger},
    doi = {10.1109/SP.2019.00063},
    url = {https://doi.ieeecomputersociety.org/10.1109/SP.2019.00063},
    publisher = {IEEE Computer Society},
    address = {Los Alamitos, CA, USA},
    month = {may}

We present Ouroboros Crypsinous, the first formally analyzed privacy-preserving proof-of-stake blockchain protocol. To model its security we give a thorough treatment of private ledgers in the (G)UC setting that might be of independent interest.

To prove our protocol secure against adaptive attacks, we introduce a new coin evolution technique relying on SNARKs and key-private forward secure encryption. The latter primitive—and the associated construction—can be of independent interest. We stress that existing approaches to private blockchain, such as the proof-of-work-based Zerocash are analyzed only against static corruptions.