CrySP Speaker Series on Privacy

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Cryptographic Locks For Cryptocurrency Payments

Sri AravindaKrishnan Thyagarajan, NTT Research

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November 2, 2022 1:00pm, in Zoom


Blockchains and their popular application of cryptocurrencies have revolutionized the payment infrastructure of the world. Users can now make trustless payments among each other without having to worry about extensive fees or hurdles. The technology has also given rise to more complex financial systems, referred to as Decentralized Finance (DeFi) systems. What has followed is the entry of numerous cryptocurrencies or DeFi systems as they are referred to, into the blockchain application space.

A natural question that arises is how do these different systems co-exist with each other. For example, a user of one cryptocurrency may want to make payments to another user who accepts tokens of a different cryptocurrency. Or, a user may want to exchange a token of one cryptocurrency with a token of another cryptocurrency. Such scenarios are trivial with centralized trusts like banks and exchange services, but require complex solutions in the blockchain setting which suffer from numerous security, privacy and cost issues. In this talk, we will see payment protocols to the above two scenarios that instead have better efficiency, sots, scalability, user-privacy and interoperability compared to existing solutions. The protocols make use of new cryptographic techniques in combination with new payment techniques to achieve these guarantees. By doing so, these protocols address several fundamental questions concerning the theoretical foundation and practical development of blockchain-based cryptocurrencies.


Sri AravindaKrishnan Thyagarajan (Aravind) is currently a Postdoc at NTT Research and was formerly a Postdoc at CMU with Elaine Shi. His primary research interest is in applied cryptography where he works on problems related to "cryptography meets game-theory” in applications like blockchains, security and privacy of payment applications in cryptocurrencies and fairness in multi-party computation. He completed his PhD in Computer Science at University of Erlangen-Nürnberg, Germany with Dominique Schröder in 2021 and Masters at Saarland University, Germany in 2016.