Steven Goldfeder will be presenting his generals May 18, 2015 at 10:15am in CS 401. The members of his committee are: Arvind Narayanan (adviser), Ed Felten, and Andrea LaPaugh. Everyone is invited to attend his talk, and those faculty wishing to remain for the oral exam following are welcome to do so. His abstract and reading list follow below. Abstract: The Bitcoin ecosystem has suffered frequent thefts and losses affecting both businesses and individuals. Due to the irreversibility, automation, and pseudonymity of transactions, Bitcoin currently lacks support for the sophisticated internal control systems deployed by modern businesses to deter fraud. While Bitcoin’s built-in mutisignature feature can be used to split control over a Bitcoin wallet and achieve access control, we show that using multisignatures leads to serious privacy and anonymity losses. To address this problem, we present the first threshold signature scheme compatible with Bitcoin’s ECDSA signatures and show how distributed Bitcoin wallets can be built using this primitive. For businesses, we show how our distributed wallets can be used to systematically eliminate single points of failure at every stage of the flow of bitcoins through the system. For individuals, we design, implement, and evaluate a two-factor secure Bitcoin wallet. Reading List: Anderson, Ross. Security engineering. John Wiley & Sons, 2008. Chapters 2, 4, 7, 10. Bonneau, Joseph, Andrew Miller, Jeremy Clark, Arvind Narayanan, Joshua A. Kroll and Edward W. Felten. “Research Perspectives and Challenges for Bitcoin and Cryptocurrencies”. To appear in IEEE Security & Privacy, 2015. De Cristofaro, Emiliano, Honglu Du, Julien Freudiger, and Greg Norcie. “Two-Factor or not Two-Factor? A Comparative Usability Study of Two-Factor Authentication.” 8th NDSS Workshop on Usable Security (USEC), 2014. Goldwasser, Shafi. "Multi party computations: past and present." In Proceedings of the sixteenth annual ACM symposium on Principles of distributed computing, pp. 1-6. ACM, 1997. Katz, Jonathan, and Yehuda Lindell. Introduction to modern cryptography. CRC Press, 2014. Langford, Susan K. "Threshold DSS signatures without a trusted party." In Advances in Cryptology—CRYPT0’95, pp. 397-409. Springer Berlin Heidelberg, 1995. Lindell, Yehuda, and Benny Pinkas. "Secure multiparty computation for privacy-preserving data mining." Journal of Privacy and Confidentiality 1, no. 1 (2009): 5. Section 3: Constructions. MacKenzie, Philip, and Michael K. Reiter. "Two-party generation of DSA signatures." In Advances in Cryptology—CRYPTO 2001, pp. 137-154. Springer Berlin Heidelberg, 2001. Meiklejohn, Sarah, Marjori Pomarole, Grant Jordan, Kirill Levchenko, Damon McCoy, Geoffrey M. Voelker, and Stefan Savage. "A fistful of bitcoins: characterizing payments among men with no names." In Proceedings of the 2013 conference on Internet measurement conference, pp. 127-140. ACM, 2013. Moore, Tyler, and Nicolas Christin. "Beware the middleman: Empirical analysis of bitcoin-exchange risk." In Financial Cryptography and Data Security, pp. 25-33. Springer Berlin Heidelberg, 2013. Nakamoto, Satoshi. "Bitcoin: A peer-to-peer electronic cash system." Shamir, Adi. "How to share a secret." Communications of the ACM 22, no. 11 (1979): 612-613. Wu, Thomas, Michael Malkin, and Dan Boneh. "Building Intrusion Tolerant Applications." In Proceedings of the 8th USENIX Security Symposium, 1999.