Presentations

2017

• Hostlie blockchain takeovers
  Presented at BITCOIN Workshop 2018
  Mar 2 2018
• Verifiable delay functions & their applications
  Presented at Systems@NYU group meeting
  Jan 19 2018
• The promise and peril of smart contracts
  Presented at Swissquote Conference 2017 on FinTech
  Lausanne, Switzerland, Nov 3 2017
• Smart contracts: a legal view
  Presented at NYU Law Privacy Research group
  New York, NY, USA, Nov 1 2017
• Technology limits for blockchains
  Panel discussion at Blockchain Economic Forum 2017
  New York, NY, USA, Oct 31 2017
• Verifiable Lotteries
  Presented at With the best: cybersecurity
  (online) Oct 15 2017
• Hostile blockchain takeovers
  Presented at Cornell Tech Blockchains Workshop
  New York, NY, USA, Oct 6 2017
• Verifiable delay functions & their applications
  Presented at NYU Tandon CSE Seminar
  Sep 22 2017
• Randomness beacons & verifiable lotteries
  Presented at 2017 Technion Summer School on Cyber & Computer Security
  Haifa, Israel, Sep 10 2017
• Ethereum Basics
  Presented at 2017 Technion Summer School on Cyber & Computer Security
  Haifa, Israel, Sep 9 2017
• Secure programming in Ethereum
  Presented at International School on Foundations of Security Analysis and Design (FOSAD)
  Bertinoro, Italy, Aug 30 2017
• Introduction to Ethereum
  Presented at International School on Foundations of Security Analysis and Design (FOSAD)
  Bertinoro, Italy, Aug 28 2017
• Introduction to Ethereum
  Presented at Swiss Blockchain Summer School
  Lausanne, Switzerland, Jun 21 2017
• Verifiable lotteries (video)
  Presented at dot Security
  Paris, France, Apr 21 2017
• Cryptography and Usability (panel)
  Organized by NEXTLEAP Seminar
  Paris, France, Apr 19 2017
• Public randomness, blockchains, and delay functions
  Presented at INRIA
  Paris, France, Apr 19 2017
• Alternatives to Bitcoin's proof-of-work
  Presented at MIT 6.892 class
  Cambridge, MA, USA, Mar 10 2017
• Alternatives to Bitcoin's proof-of-work
  Presented at MIT 6.892 class
  Cambridge, MA, USA, Mar 10 2017
• Public randomness, blockchains, and delay functions
  Presented at Hebrew University
  Jerusalem, Israel, Mar 1 2017
• Public randomness, blockchains, and delay functions
  Presented at Technion - Israel Institute of Technology
  Haifa, Israel, Feb 26 2017
• Public randomness, blockchains, and delay functions
  Presented at Chinese University of Hong Kong
  Shatin, Hong Kong, Jan 26 2017
• Bitcoin Mining, Network and Economics
  Presented at theWinter School on Cryptocurrency and Blockchain Technologies
  Shanghai, China, Jan 15 2017
• Bitcoin Overview
  Presented at theWinter School on Cryptocurrency and Blockchain Technologies
  Shanghai, China, Jan 15 2017

2016

• Challenges in secure messaging
  Presented at EE 380 Computer Systems Colloquium
  Stanford, CA, Nov 30 2016
• Public randomness, blockchains, and delay functions
  Presented at Sungkyunkwan University
  Seoul, South Korea, Nov 23 2016
• Public randomness, blockchains, and delay functions
  Presented at MIT Cryptography and Information Security Seminar Series
  Cambridge, MA, Nov 18 2016
• Incentives in cryptocurrencies
  Presented at ECRYPT Workshop on Cryptocurrencies
  Athens, Greece, June 3 2016
• Bitcoin mining
  Presented at IACR Summer School on Blockchain Technologies
  Corfu, Greece, May 30 2016
• Bitcoin overview
  Presented at IACR Summer School on Blockchain Technologies
  Corfu, Greece, May 30 2016
• Solvency proofs for Bitcoin exchanges
  Presented at Stanford Computer Forum Annual Meeting
  Palo Alto, CA, USA, Apr 11 2016
• The Future of Bitcoin and Cryptocurrencies
  Panel at 2016 RSA Conference
  San Francisco, CA, USA, Mar 2 2016
• EthIKS: Using Ethereum to audit a CONIKS key transparency log
  Presented at BITCOIN '16
  Bridgetown, Barbados, Feb 26 2016
• Why buy when you can rent? Bribery attacks on Bitcoin consensus
  Presented at BITCOIN '16
  Bridgetown, Barbados, Feb 26 2016
• Strong passwords
  Guest talk at Clever
  San Francisco, CA, USA, Feb 1 2016

2015

• Provisions: Privacy-preserving proofs of solvency for Bitcoin exchanges
  École Normale Supérieure
  Paris, France, Nov 27 2015
• CONIKS & Secure Messaging
  Institut national de recherche en informatique et en automatique (INRIA)
  Paris, France, Nov 26 2015
• Provisions: Privacy-preserving proofs of solvency for Bitcoin exchanges
  École polytechnique fédérale de Lausanne (EPFL)
  Lausanne, Switzerland, Nov 25 2015
• Provisions: Privacy-preserving proofs of solvency for Bitcoin exchanges
  Berkeley Security Seminar
  Berkeley, CA, USA, Oct 23 2015
• Provisions: Privacy-preserving proofs of solvency for Bitcoin exchanges
  ACM CCS
  Denver, CO, USA, Oct 14 2015
• Provisions: Privacy-preserving proofs of solvency for Bitcoin exchanges
  Stanford Security Seminar
  Palo Alto, CA, USA, Oct 7 2015
• Involving academia in Bitcoin research
  Scaling Bitcoin
  Montreal, QC, Canada, Sep 12 2015
• Open questions about Bitcoin and related cryptocurrencies
  Guest lecture, CS294 UC Berkeley
  Berkeley, CA, Sep 2 2015
• Wrecking Bitcoin consensus with large transactions
  USENIX Security (rump session)
  Washington, DC, USA, Aug 12 2015
• Decentralizing Prediction Markets
  Silicon Valley Etherium Meetup
  San Francisco, CA, USA, Jun 11 2015
• Emerging questions in secure messaging
  Security and Human Behavior
  Washington, DC, USA, Jun 8 2015
• Does Bitcoin consensus actually work?
  Presented at SRI
  Menlo Park, CA, USA, Jun 3 2015
• Research Perspectives and Challenges for Bitcoin and Cryptocurrencies
  IEEE Security & Privacy
  San Jose, CA, USA, May 20 2015
• Building a public key directory with verifiable global consistency
  Security Seminar, University of Washington
  Seattle, WA, USA, May 4 2015
• Recent developments in end-to-end encrypted messaging tools: CONIKS and more
  Stanford Computer Forum Security Workshop
  Palo Alto, CA, USA, Apr 27 2015
• Towards reliable storage of 56-bit secrets in human memory
  Stanford Security Lunch
  Palo Alto, CA, USA, Apr 15 2015
• CONIKS
  Bay Area Security Research Summit
  San Francisco, CA, USA, Apr 10 2015
• Bitcoin security (panel discussion)
  Presented at San Francisco Bitcoin meetup
  San Francisco, CA, USA, Mar 28 2015
• HSTS and HPKP in practice (video)
  Presented at IETF 92
  Dallas, TX, USA, Mar 26 2015
• Towards reliable storage of 56-bit secrets in human memory
  Presented at Southern Methodist University
  Dallas, TX, USA, Mar 25 2015
• Technical aspects of blockchain-based applications (panel discussion)
  Presented at Stanford Blockchain Workshop
  Palo Alto, CA, USA, Mar 23 2015
• Making universal encryption usable
  Presented at the NIST Cybersecurity and Consumer Protection Summit
  Palo Alto, CA, USA, Feb 12 2015
• Innovation in Secure Messaging
  Presented at Carnegie Mellon University
  Pittsburgh, PA, USA, Feb 4 2015
• Advanced HTTPS Security: HSTS and pinning
  Presented to the Internet Architecture Board
  (online) Jan 14 2015
• Innovation in end-to-end encrypted communication
  Presented at Real World Crypto
  London, UK, Jan 9 2015

2014

• Bitcoin as a public randomness source
  Stanford Security Seminar
  Palo Alto, CA, USA, Dec 1 2014
• Storing 56-bit keys in human memory
  Presented as a ECE Colloquium, Rutgers University
  New Brunswick, NJ, USA, Nov 19 2014
• Panel discussion
  UK-US Cybersecurity Symposium
  Boston, MA, USA, Oct 31 2014
• Advanced HTTPS Security
  Princeton Office of Information Technology
  Princeton, NJ, USA, Oct 29 2014
• Bringing cognitive science to computer security: Helping users memorize random passwords
  Cognitive Science Research Seminar
  Princeton, NJ, USA, Oct 22 2014
• Upgrading HTTPS in midair: HSTS and key pinning in practice
  Presented at ETH Zürich
  Zurich, Switzerland, Oct 10 2014
• Bitcoin as a public randomness source
  Presented at Ruhr-Universität Bochum
  Bochum, Germany, Oct 9 2014
• Upgrading HTTPS in midair: HSTS and key pinning in practice
  Presented at the Universität Bonn
  Bonn, Germany, Oct 6 2014
• Storing 56-bit keys in human memory
  Presented at the COSIC Seminar Series KU Leuven
  Belgium, Oct 3 2014
• Bitcoin as a public randomness source
  Cambridge Security Seminar Series
  Cambridge, UK, Sep 30 2014
• Why buy when you can rent? Bribery attacks on Bitcoin
  Presented at USENIX Security 2014 (works-in-progress session)
  San Diego, CA, USA, Aug 20 2014
• EFFCUP and developments in secure messaging (with Kurt Opsahl)
  Presented at USENIX Summit on Hot Topics in Security 2014
  San Diego, CA, USA, Aug 19 2014
• Better in Practice than in Theory: Lessons from the Rise of Bitcoin (with Arvind Narayanan)
  Presented at USENIX Summit on Hot Topics in Security 2014
  San Diego, CA, USA, Aug 19 2014
• Toward reliable storage of 56-bit secrets in human memory (video)
  Presented at the University of Waterloo
  Waterloo, ON, Canada, July 24 2014
• Toward reliable storage of 56-bit secrets in human memory (lightning talk)
  Presented at SOUPS 2014: The Tenth Symposium On Usable Privacy and Security
  Menlo Park, CA, USA, July 10 2014
• Privacy concerns of implicit secondary factors for web authentication
  Presented at WAY 2014: Adventures in Authentication Workshop
  Menlo Park, CA, USA, July 9 2014
• Why buy when you can rent? Bribery attacks on Bitcoin
  Presented at WEIS 2014: The 13th Workshop on the Economics of Information Security (rump session)
  State College, PA, USA, Jun 23 2014
• The future of web authentication
  Presented at the Concordia University
  Montreal, QC, Canada, Apr 23 2014
• Tutorial on Bitcoin technologies
  Presented at the Electronic Frontier Foundation
  San Francisco, CA, USA, Apr 9 2014
• Tutorial on Bitcoin technologies (video)
  Presented at the Bitcoin and Cryptocurrency Research Conference
  Princeton, NJ, USA, Mar 27 2014
• FawkesCoin: Bitcoin with public-key cryptography
  Presented at the Security Protocols Workshop
  Cambridge, UK, Mar 21 2014
• An Overview of Bitcoin, or "Bitcoin is a Full-Employment Act for Security Engineers"
  Cambridge Security Seminar Series
  Cambridge, UK, March 18 2014
• Fixing HTTPS: New models for distributing transport security policy
  Presented at Center For Information Technology Policy
  Princeton, NJ, USA, Mar 13 2014
• Mixcoin: Anonymity for Bitcoin with accountable mixes
  Presented at Financial Crypto
  Bridgetown, Barbados, Mar 6 2014
• Estimating the power consumption of Bitcoin
  Presented at Financial Crypto (rump session)
  Bridgetown, Barbados, Mar 4 2014

2013

• The science of guessing: analyzing an anonymized corpus of 70 million passwords
  Presented at the NSA Science of Cybersecurity Award Reception
  Ft Meade, MD, USA, July 17 2013
• S-links: Why distributed security policy requires secure introduction
  Presented at W2SP
  San Francisco, CA, USA, May 24 2013
• Pins, Tacks, and Slinks: Proposals for patching PKI on the web
  Cambridge Security Seminar Series
  Cambridge, UK, May 8 2013
• Scalable distribution of HTTPS security policies
  Presented at ISSNet workshop
  Victoria, BC, Canada, Apr 24 2013
• Web authentication in practice
  Presented at ISR, Carnegie Mellon University
  Pittsburgh, PA, USA, Feb 22 2013
• What I've learned about passwords, and why they aren't going away (video)
  Presented at Mozilla
  San Francisco, CA, USA, Feb 4 2013

2012

• Authenticating humans to computers: What I expect for the next 10 years (video)
  Presented at Center of Information Technology Policy
  Princeton, NJ, USA, Nov 29 2012
• The under-utilised effectiveness of computer science in other research fields
  Presented at Gates Cambridge Idea Lab
  Cambridge, UK, June 11 2012
• Guessing human-chosen secrets
  Presented at Security and Human Behavior 2012
  New York, NY, USA, June 4 2012
• Of contraseñas, סיסמאות, and 密码: Character encoding issues for web passwords
  Presented at Web 2.0 Security & Privacy
  San Francisco, CA, USA, May 24 2012
• The science of guessing: analyzing an anonymized corpus of 70 million passwords
  Presented at the 2012 IEEE Symposium on Security and Privacy
  San Francisco, CA, USA, May 23 2012
• Guessing human-chosen secrets
  Presented at the University of Münster
  Münster, Germany, May 8 2012
• Authentication in a networked world
  Presented at the Gates Scholars' Easter Term Symposium
  Cambridge, UK, May 2 2012
• Big Data Lecture #2
  Presented in Part II Additional Topics
  Cambridge, UK, Apr 30 2012
• Big Data Lecture #1
  Presented in Part II Additional Topics
  Cambridge, UK, Apr 27 2012
• Guessing human-chosen secrets
  Presented at Microsoft Research
  Redmond, WA, USA, Apr 23 2012
• Statistical metrics for individual password strength
  Presented at Twentieth International Workshop on Security Protocols
  Cambridge, UK, Apr 12 2012
• Guessing human-chosen secrets
  Presented at Microsoft Research
  Cambridge, UK, Apr 5 2012
• It’s Not Stealing If You Need It: A panel on the ethics of performing research using public data of illicit origin
  (with Serge Egelman, Sonia Chiasson, David Dittrich and Stuart Schechter)
  Panel discussion at WECSR '12: Workshop on Ethics in Computer Security Research
  Kralendijk, Bonaire, Netherlands, Mar 2 2012
• Linguistic properties of multi-word passphrases
  Presented at USEC '12: Workshop on Usable Security.
  Kralendijk, Bonaire, Netherlands, Mar 2 2012
• Questions to which the answer is no (passwords edition)
  Presented at FC'12: The Sixteenth International Conference on Financial Cryptography and Data Security (rump session)
  Kralendijk, Bonaire, Netherlands, Feb 27 2012
• A birthday present every eleven wallets? The security of customer-chosen banking PINs
  Presented at FC'12: The Sixteenth International Conference on Financial Cryptography and Data Security
  Kralendijk, Bonaire, Netherlands, Feb 27 2012
• User authentication on the web
  Guest lecture for Part II Security course
  Cambridge, UK, Feb 22 2012.
• User choice of PINs and passphrases
  Cambridge Security Seminar Series
  Cambridge, UK, Jan 24 2012

2011

• Getting web authentication right
  Presented at the Nineteenth International Workshop on Security Protocols
  Cambridge, UK, Mar 28 2011.

2010

• Authentication in the Social Web
  Presented at the Workshop on the future of social networking
  Cambridge, UK, Nov 18 2010.
• Human authentication on the web
  Guest lecture for Part II Security course
  Cambridge, UK, Nov 17 2010.
• Side Channel Cryptanalysis
  Presented at the Current Research Topics Lecture Series
  Cambridge, UK, Nov 5 2010
• The challenges of online protest
  Presented at the 2010 Festival of Ideas
  Cambridge, UK, Oct 23 2010
• Human-generated secret data
  Presented at Security and Human Behaviour 2010
  Cambridge, UK, Jun 29 2010
• Cryptographic implementation attacks
  Presented to Checkpoint Security
  Cambridge, UK, Jun 25 2010
• Security and social networks
  Presented to Checkpoint Security
  Cambridge, UK, Jun 22 2010
• The challenges of online protest
  Presented at the Third Annual Global Scholars' Symposium
  Cambridge, UK, Jun 12 2010
• Passwords and intimacy
  Presented at the WEIS 2010: The Ninth Workshop on the Economics of Information Security (rump session)
  Cambridge, MA, USA, Jun 8 2010
• The password thicket: technical and market failures in human authentication on the web
  Presented at the WEIS 2010: The Ninth Workshop on the Economics of Information Security
  Cambridge, MA, USA, Jun 7 2010 (paper)
• Side Channel Cryptanalysis
  Presented at the Current Research Topics Lecture Series
  Cambridge, UK, May 4 2010
• New Directions in Online Protest
  Presented at the Eighteenth International Workshop on Security Protocols
  Cambridge, UK, Mar 24 2010
• Internet Censorship and Resistance
  Presented at the Gates Scholars' Lent Symposium 2010
  Cambridge, UK, Feb 2 2010
• New Directions in Online Protest
  Presented at FC'10: The Fourteenth International Conference on Financial Cryptography and Data Security (rump session)
  Tenerife, Spain, Jan 26 2010
• What's in a Name? Evaluating Statistical Attacks on Personal Knowledge Questions
  Presented at FC'10: The Fourteenth International Conference on Financial Cryptography and Data Security
  Tenerife, Spain, Jan 26 2010 (paper)
• Statistical Attacks on Personal Knowledge Questions
  Presented at Computer Laboratory Security Group meeting
  Cambridge, UK, Jan 22 2010

2009

• Security and Privacy in Social Networks
  Presented to the EFF
  San Francisco, CA, USA, Dec 21 2009.
• Security and Personal Knowledge
  Presented to security research group
  University of Hertfordshire, Hatfield, UK, Dec 2 2009
• Security and Social Networks
  Guest Lecture for Part II Security course
  Cambridge, UK, Nov 23 2009
• Security and Social Networks
  Presented at the SPION Workshop
  Katholieke Universiteit Leuven, Belgium, Nov 5 2009
• Security and Personal Knowledge
  Presented to COSIC research group
  Katholieke Universiteit Leuven, Belgium, Nov 4 2009
• Security and Social Networks
  Presented to Checkpoint Security
  Cambridge, UK, Sep 7 2009
• Prying Data out of a Social Network (talk cancelled, slides only)
  Presented at ASONAM 2009: The 2009 International Conference on Social Network Analysis and Mining
  Athens, Greece, Jul 20 2009 (paper)
• Privacy Suites: Shared Privacy For Social Networks (poster)
  Presented at SOUPS 2009: The Fifth Symposium On Usable Privacy and Security
  Mountain View, CA, USA, Jul 15 2009 (abstract)
• Privacy Aspects of Social Graphs
  Stanford Security Seminar series
  Palo Alto, CA, USA, Jul 14 2009
• Can Privacy Be Viral?
  Presented at WEIS 2009: The Eighth Workshop on the Economics of Information Security (rump session)
  London, UK, Jun 25 2009
• The Privacy Jungle: On the Market for Privacy in Social Networks
  Presented at the WEIS 2009: The Eighth Workshop on the Economics of Information Security
  London, UK, Jun 24 2009 (paper)
• Security and Social Context
  Presented at the 2009 Workshop on Security and Human Behaviour
  Cambridge, MA, USA, Jun 12 2009
• Internet Censorship and Resistance
  Presented at the 2009 Churchill College Conference on Everything
  Cambridge, UK, May 15 2009
• Unique Security Challenges for Online Social Networks (Invited Talk)
  Presented at FORWARD 2009: The Second ICT-FORWARD Workshop
  Saint-Jean-Cap-Ferrat, France, May 4 2009 (talk abstract)
• Alice and Bob in Love: Cryptographic Communication Using Natural Entropy
  Presented at the Seventeenth International Workshop on Security Protocols 2009
  Cambridge, UK, Apr 2 2009 (paper)
• Eight Friends are Enough: Social Graph Approximation via Public Listings
  Presented at SocialNets 2009: The Second ACM Workshop on Social Network Systems
  Nurembeg, Germany, Mar 31 2009 (paper)
• Privacy Implications of Public Listings on Social Networks
  Cambridge Security Seminar Series
  Cambridge, UK, Mar 24 2009 (paper)
• Privacy Implications of Social Networks
  Presented at the Gates Scholars' Lent Symposium 2009
  Cambridge, UK, Mar 1 2009