SoK: A Systematic Study of Anonymity in Cryptocurrencies

Blockchain and cryptocurrencies have been widely deployed and used in our daily life. Although there are numerous works in the literature surveying technical challenges and security issues in blockchains, very few works focused on the anonymity guarantees provided in cryptocurrencies. In this work, we conduct a systematic survey on anonymity in cryptocurrencies with a clear categorization for the different tiers of anonymity offered in the various cryptocurrencies as well as their known weaknesses and vulnerabilities. We also study the techniques that have been used to achieve each tier of anonymity. Finally, we asses the current techniques, and present a forecast for the technological trends in this field.