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Special Topics on Privacy and Public Auditability — Event 4

Featured topics: anonymous credentials, blind signatures, private authentication.

Structure: welcome; three invited talks; panel conversation.

Date and time: November 21st, 2022, 09:00–12:30 EST

[Note: it was postponed to Nov 21st, after an initial scheduling for October 31st]

Location/format: virtual event over Webex video conference

Attendance: open and free to the public, upon registration

  • 09:00--09:10: STPPA #4 intro
  • 09:10--09:55: Invited talk: Anonymous Credentials, by Anna Lysyanskaya (Brown University, USA),
  • 09:55--10:40: Invited talk: Blind Signatures: Past, Present, and Future, by Julian Loss (CISPA, Germany)
  • 10:40--10:55: Break
  • 10:55--11:40: Invited talk: Challenges and new Features for Anonymous Credentials: Revocation and Decentralization, by Foteini Baldimtsi (George Mason University, USA)
  • 11:40--12:30: Panel conversation (with the three invited speakers, moderated by NIST-PEC)

List of invited speakers:

  • Anna Lysyanskaya (Brown University, USA)
  • Julian Loss (CISPA, Germany)
  • Foteini Baldimtsi (George Mason University, USA)

List of bios (provided by the speakers):

Anna Lysyanskaya is a Professor of Computer Science at Brown University, which she joined in 2002 after receiving her Ph.D. from MIT.  A theme of her academic research is on balancing privacy with accountability, and specifically allowing users to prove that they are authorized even while not revealing any additional information about themselves.  Professor Lysyanskaya is a recipient of numerous awards from the National Science Foundation, as well as industry grants from IBM, Google, and Facebook. She has served on the Board of Directors of the International Association for Cryptologic Research (IACR)  since 2012, and will serve as co-Chair of the annual Crypto conference in 2023.

Foteini Baldimtsi is an Assistant Professor in the Computer Science Department at George Mason University. She received her Ph.D. from Brown University in May 2014 and worked as a postdoctoral researcher in Boston University and University of Athens. Her research interests are in the areas of cryptography, security and data privacy. She focuses on designing provably secure cryptographic schemes for a variety of applications such as privacy preserving identity management and private and scalable blockchain transactions. She is a recipient of an NSF CAREER award as well as Google, IBM and Facebook faculty awards.

Julian Loss is a tenure-track faculty at CISPA Helmholtz Center for Information Security in Saarbrücken, Germany. After receiving his PhD from Ruhr University Bochum in 2019, he spent two years as a postdoc at the University of Maryland and Carnegie Mellon University.His research interests are in the area of cryptography and its intersection with distributed computing. Besides digital signatures, he has worked on problems such as distributed consensus, distributed clock synchronization, and is known for co-introducing the now widely-used algebraic group model.His work on the ROS problem won a best paper award at EUROCRYPT 2021.

About STPPA: In the "Special Topics on Privacy and Public Auditability" series, the NIST privacy-enhancing cryptography (PEC) project hosts talks on various interconnected topics related to privacy and public auditability. The goal is to convey basic technical background, incite curiosity, suggest research questions and discuss applications, with an emphasis on the role of cryptographic tools.

Selected Presentations
November 21, 2022 Type
9:00 AM STPPA#4 Welcoming
Luís T. A. N. Brandão - NIST/Strativia

Welcoming and introduction to STPPA #4

9:10 AM Anonymous credentials
Anna Lysyanskaya - Brown University

Abstract: When accessing a service, we often need to present authorization credentials. Anonymous credentials allow users to do so without revealing any information about themselves, other than the fact that they are indeed authorized; moreover, different showings of the same anonymous credential cannot be linked to each other.  Thus, even if a service provider's records are somehow leaked, or aggregated together with other service providers' records, users still cannot be traced through the system.  This talk will be an overview of the state-of-the-art of anonymous credentials: what privacy and security guarantees they can provide, and what accountability mechanisms they are compatible with.

9:55 AM Blind Signatures: Past, Present, and Future
Julian Loss - CISPA (Germany)

Abstract: Blind signatures are one of the fundamental tools for privacy sensitive applications. Although blind signatures were historically developed for traditional electronic cash systems, they have since found numerous use cases and have recently received renewed attention in the context of blockchain systems. In my talk, I will give an overview over the rich history of this fascinating primitive spanning from the early eighties to the present day. I will also discuss some of the major challenges that remain for blind signatures today.


10:55 AM Challenges and new Features for Anonymous Credentials: Revocation and Decentralization
Foteini Baldimtsi - George Mason University

Abstract: In this talk I will discuss some of the main challenges of anonymous authentication. I will focus on revocation of credentials, the challenge of doing so in a privacy preserving manner and how cryptographic tools like accumulators can help. Then, I will talk about ways to decentralize anonymous credentials via the use of blockchain and will discuss proposals and challenges.


11:40 AM STPPA#4 Panel: Privacy and Public Auditability
Foteini Baldimtsi - George Mason University
Julian Loss - CISPA (Germany)
Anna Lysyanskaya - Brown University
Luís T. A. N. Brandão - NIST/Strativia
René Peralta - NIST
Angela Robinson - NIST

After three talks by renowned experts in the areas of anonymous credentials and private authentication, followed a panel conversation with the three speakers and the NIST-PEC team.


Event Details

Starts: November 21, 2022 - 09:00 AM EST
Ends: November 21, 2022 - 12:30 PM EST

Format: Virtual Type: Other


Attendance Type: Open to public
Audience Type: Industry,Government,Academia,Other

Parent Project

See: Privacy-Enhancing Cryptography

Related Topics

Security and Privacy: cryptography

Created September 16, 2022, Updated December 28, 2022