Nicholas J. Hopper

Assistant Professor
Computer Science & Engineering Department
University of Minnesota
hopper at cs umn edu

Office:
EECS 4-211
(612)-626-1284 
Shortcuts: Research interests | Papers | Teaching | Etc...


Research

My general interests are in cryptography, computer & network security, and theoretical computer science.   The focus of my research is on proving the security of computer systems and protocols.  The central questions in this research are:

I have had the privilege of working on these subjects with many bright students.

Papers

In submission

Please send e-mail if you are interested in any of the following:

Peng Wang, Ivan Osipkov, Nicholas Hopper, and Yongdae Kim.  "Myrmic: Provably secure and efficient DHT routing," 2007. (An earlier tech report is available here.)

Peng Wang, James Tyra, Tyson Malchow, Yongdae Kim, Nicholas Hopper, Denis Foo Kune, and Eric Chan-Tin.  "Attacking the Kad Network," 2007.

Peer-reviewed Conference/Workshops

Jon McLachlan and Nicholas Hopper. "Don't Clog the Queue: Circuit Clogging and Mitigation in P2P anonymity schemes," at Financial Crypto 2008.

Nicholas Hopper, Eugene Y. Vasserman, and Eric Chan-Tin. "How much anonymity does network latency leak?" at CCS 2007.

Eugene Vasserman, Nicholas Hopper, John Laxson, and James Tyra.  "SilentKnock: Practical and Provably Undetectable Authentication." at ESORICS 2007.

Ivan Osipkov, Eugene Vasserman, Nicholas Hopper and Yongdae Kim. "Combatting Double-Spending Using Cooperative P2P Systems." at ICDCS 2007.

Nicholas Hopper, David Molnar, and David Wagner.  "From Weak to Strong Watermarking." at 4th Theoretical Cryptography Conference: TCC 2007.  (Full version)

Nicholas Hopper and Eugene Vasserman. "On the effectiveness of k-anonymity against traffic analysis and surveillance," at Privacy in the Electronic Society: WPES 2006.

Luis von Ahn, Andrew Bortz, Nicholas Hopper, and Kevin O'Neill.  "Selectively Traceable Anonymity," at Privacy Enhancing Technologies: PET 2006.

Ivan Osipkov, Peng Wang, Nicholas Hopper and Yongdae Kim.  "Robust Accounting in Decentralized P2P Storage Systems," at ICDCS 2006.

Jung Hee Cheon, Nicholas Hopper, Yongdae Kim and Ivan Osipkov.  "Authenticated Key-Insulated Public Key Encryption and Timed-Release Cryptography," at Financial Crypto 2006.

Nicholas Hopper. "On Steganographic Chosen Covertext Security," at ICALP 2005.

Luis von Ahn, Nicholas J. Hopper, and John Langford. "Covert Two-Party Computation," at STOC 2005.

Luis von Ahn and Nicholas J. Hopper. " Public-Key Steganography," at Eurocrypt 2004.

Luis von Ahn, Andrew Bortz, and Nicholas J. Hopper. "k-Anonymous Message Transmission," at CCS 2003.

Luis von Ahn, Manuel Blum, Nicholas J. Hopper and John Langford. " CAPTCHA: Using Hard AI Problems for Security," at Eurocrypt 2003.

Nicholas J. Hopper, John Langford, and Luis Von Ahn. " Provably Secure Steganography," at Crypto 2002.

Nicholas J. Hopper and Manuel Blum. " Secure Human Identification Protocols," at Asiacrypt 2001.

Nicholas J. Hopper, Sanjit A. Seshia, and Jeanette M. Wing, "Combining Theory Generation and Model Checking for Security Protocol Analysis," at Formal Methods in Computer Security, July 2000. Also available as CMU Technical Report CMU-CS-00-107, January 2000.

Nicholas Freitag McPhee and Nicholas J. Hopper. " Analysis of Genetic Diversity through Population History," in GECCO99: Proceedings of the Genetic and Evolutionary Computation Conference, July 1999.

Nicholas Freitag McPhee and Nicholas J. Hopper. " AppGP: An alternative structural representation for GP," in Proceedings of the 1999 Congress on Evolutionary Computation, June 1999.

Nicholas Freitag McPhee, Nicholas J. Hopper, and Mitchell L. Reierson. " Impact of types on essentially typeless problems in GP," in Genetic Programming 1998: Proceedings of the Third Annual Conference, July 1998.

Other

Nicholas J. Hopper. "Toward a Theory of Steganography," CMU Ph.D. Thesis, 2004.

Nicholas J. Hopper and Manuel Blum, "A Secure Human-Computer Authentication Scheme", CMU Technical Report CMU-CS-00-139, May 2000.


Teaching

At Minnesota:
Spring 2008 - CSci 5403: Complexity Theory.
Fall 2007 - CSci 5271: Introduction to Computer Security.
Spring 2007 - CSci 4011: Formal Languages and Automata Theory.
Fall 2006 -  CSci 5271: Introduction to Computer Security.
Spring 2006 -  CSci 4011: Formal Languages and Automata Theory.
Fall 2005 -  CSci 5271: Introduction to Computer Security.
Spring 2005 -  CSci 8980: Advanced Cryptography.

At CMU:
Spring 2003 - 15-859I Theoretical Aspects of Cryptography
Fall 2001 -  15-827 Security and Cryptography
Fall 2000 -  15-451 Algorithms

Etc.