@misc{15714, keywords = {Zero knowledge, cryptographic protocols / anonymity, cryptocurrencies}, author = {Prastudy Fauzi and Sarah Meiklejohn and Rebekah Mercer and Claudio Orlandi}, title = {Quisquis: A New Design for Anonymous Cryptocurrencies}, abstract = {Despite their usage of pseudonyms rather than persistent identifiers, most existing cryptocurrencies do not provide users with any meaningful levels of privacy. This has prompted the creation of privacy-enhanced cryptocurrencies such as Monero and Zcash, which are specifically designed to counteract the tracking analysis possible in currencies like Bitcoin. These cryptocurrencies, however, also suffer from some drawbacks: in both Monero and Zcash, the set of potential unspent coins is always growing, which means users cannot store a concise representation of the blockchain. Additionally, Zcash requires a common reference string and the fact that addresses are reused multiple times in Monero has led to attacks to its anonymity.In this paper we propose a new design for anonymous cryptocurrencies, Quisquis, that achieves provably secure notions of anonymity. Quisquis stores a relatively small amount of data, does not require trusted setup, and in Quisquis each address appears on the blockchain at most twice: once when it is generated as output of a transaction, and once when it is spent as input to a transaction. Our result is achieved by combining a DDH-based tool (that we call updatable keys) with efficient zero-knowledge arguments.}, year = {2019}, journal = {Advances in Cryptology {\textendash} ASIACRYPT 2019}, volume = {11921}, pages = {649 - 678}, publisher = {Springer International Publishing}, address = {Cham}, issn = {0302-9743}, isbn = {978-3-030-34577-8}, url = {https://link.springer.com/chapter/10.1007\%2F978-3-030-34578-5_23}, doi = {10.1007/978-3-030-34578-5_23}, editor = {Steven Galbraith and Shiho Moriai}, }