Rafail Ostrovsky

Professor of Computer Science and, by courtesy, of Mathematics
Director of Center for Information and Computation Security
UCLA, Los Angeles, CA 90095
I am interested in all aspects of theory of computation, especially in cryptography, network algorithms, and analysis and classification of high-dimensional data. Examples of topics include biometric-based cryptography, fault-tolerance, multi-party computation, zero-knowledge, algorithms for high-dimensional geometric problems such as clustering and nearest-neighbor search, metric embeddings, and routing and flow control in communication networks. Below, is a more detailed list of topics.

Cryptography:
Geometric Search and Analysis of High-Dimensional Data:
- Metric embedding, and Nearest-Neighbor Proximity Problems for High-Dimensional Data
- Clustering Algorithms for High-Dimensional Data
Distributed Control Theory, Network Algorithms and Combinatorial Algorithms:

My work has been supported in part by NSF, Teradata, Intel, John B. Garrick Foundation, OKAWA research award, Xerox Innovation group Award and IBM Faculty Award.

* Publications (in a chronological order) * Contact info * Bio * Teaching * Interested in working with me? * In popular press *

Additional bibliographic information can be found at DBLP. You can also try Google Scholar.

Publications (by topic)

Publications: Cryptography

Private Information Retrieval, Privacy-preserving datamining, and Searching on Encrypted Data

Reza Curtmola, Juan Garay, Seny Kamara, and Rafail Ostrovsky Searchable Symmetric Encryption: Improved Definitions and Efficient Constructions In Proceedings of the 13th ACM Conference on Computer and Communications Security (CCS 2006). In addition, you can get a powerpoint presentation.
Rafail Ostrovsky, William Skeith. Private Searching on Streaming Data , Preliminary version in Proceedings of Advances in Cryptology, (CRYPTO-2005) Springer-Verlag/IACR Lecture Notes in Computer Science. Updated full version accepted to Journal of Cryptography, to appear in 2007. In addition, you can get a powerpoint presentation.
Yuval Ishai, Eyal Kushilevitz, Rafail Ostrovsky Sufficient Conditions for Collision-Resistant Hashing, In Proceedings of Second Theory of Cryptography Conference (TCC-2005)Springer-Verlag Lecture Notes in Computer Science, 2005.
Yuval Isahi, Eyal Kushilevitz, Rafail Ostrovsky, Amit Sahai Batch Codes and Their Applications, In Proceedings of the ACM 2004 Symposium on Theory of Computing (STOC-2004).
Dan Boneh, Giovanni Di Crescenzo, Rafail Ostrovsky, Guiseppe Persiano Public Key Encryption with Keyword Search, In Proceedings of Advances in Eurocrypt, (EUROCRYPT-2004) Springer-Verlag/IACR Lecture Notes in Computer Science.
Eyal Kushilevitz, Rafail Ostrovsky One-way Trapdoor Permutations Are Sufficient for Non-Trivial Single-Server Private Information Retrieval , In Proceedings of Advances in Cryptology (EUROCRYPT-2000) Springer-Verlag Lecture Notes in Computer Science.
Giovanni Di Crescenzo, Tal Malkin, and Rafail Ostrovsky Single Database Private Information Retrieval Implies Oblivious Transfer , In Proceedings of Advances in Cryptology (EUROCRYPT-2000) Springer-Verlag Lecture Notes in Computer Science.
Giovanni De-Crescenzo, Yuval Ishai, Rafail Ostrovsky Universal Service-Providers for Database Private Information Retrieval , In Proceedings of Seventeenth Annual ACM Symposium on Principles of Distributed Computing (PODC-98). Journal version appears in Journal of Cryptology 14(1): 37-74 (2001).
Eyal Kushilevitz, Rafail Ostrovsky Replication Is Not Needed: Single Database, Computationally-Private Information Retrieval , In Proceedings of Thirty-eighth Annual IEEE Symposium on the Foundations of Computer Science (FOCS-97).
Rafail Ostrovsky, Victor Shoup Private Information Storage , In Proceedings of The Twenty-Ninth ACM Symposium on Theory of Computing (STOC-97).
Rafail Ostrovsky Software Protection and Simulation on Oblivious RAMs. , M.I.T. Ph.D. Thesis, 1992. Preliminary version appeared in Proceedings of 22nd annual ACM Symposium on Theory of Computing (STOC-90) pp. 514-523. Journal version appeared in the Journal of the JACM, Vol. 43, No. 3, May 1996, pp.431-473. written jointly with Oded Goldreich.

Zero Knowledge, Non-Interactive Zero-Knowledge, Knowledge Complexity

Yuval Isahi, Eyal Kushilevitz, Rafail Ostrovsky, Amit Sahai Zero-Knowledge from Secure Multiparty Computation, In Proceedings of the ACM 2007 Symposium on Theory of Computing (STOC-2007).
Jens Groth, Rafail Ostrovsky, Amit Sahai. Non-interactive Zaps and New Techniques for NIZK, In Proceedings of Advances in Cryptology, (CRYPTO-2006) Springer-Verlag/IACR Lecture Notes in Computer Science.
Jens Groth, Rafail Ostrovsky, Amit Sahai. Perfect Non-Interactive Zero Knowledge for NP, In Proceedings of Advances in Eurocrypt, (EUROCRYPT-2006) Springer-Verlag/IACR Lecture Notes in Computer Science.
Jonathan Katz, Rafail Ostrovsky, Michael O. Rabin Identity-Based Zero-Knowledge, In Proceedings of Security in Communication Networks: 4th International Conference, SCN-2004 Springer-Verlag Lecture Notes in Computer Science.
Alfredo De Santis, Giovanni Di Crescenzo, Rafail Ostrovsky, Giuseppe Persiano, Amit Sahai Robust Non-Interactive Zero Knowledge, In Proceedings of Advances in Cryptology, (CRYPTO-2001) Springer-Verlag/IACR Lecture Notes in Computer Science.
Giovanni Di Crescenzo and Rafail Ostrovsky On Concurrent Zero-Knowledge with Pre-Processing , In Proceedings of Advances in Cryptology (CRYPT0-99), Springer-Verlag Lecture Notes in Computer Science.
Oded Goldreich, Rafail Ostrovsky, Erez Petrank Computational Complexity and Knowledge Complexity. , Preliminary version in the Twenty-sixth ACM Symposium on Theory of Computing (STOC-94) Full version in SIAM Journal on Computing, 27(4):1116-1141, 1998.
Rafail Ostrovsky, Ramarathnam Venkatesan, Moti Yung Interactive Hashing Simplifies Zero-Knowledge Protocol Design. , In Proceedings of (EUROCRYPT-93) Springer Verlag.
Rafail Ostrovsky, Avi Wigderson One-Way Functions are Essential for Non-Trivial Zero-Knowledge. , In Proceedings of the second Israel Symposium on Theory of Computing and Systems} (ISTCS-93).
Moni Naor, Rafail Ostrovsky, Ramarathnam Venkatesan, Moti Yung. Perfect Zero-Knowledge Arguments for NP Can Be Based on General Complexity Assumptions. , Preliminary version in Proceedings of advances in cryptology (CRYPTO-92) Springer-Verlag Lecture Notes in Computer Science. Journal version in J. of Cryptology, 1988.
Joan Feigenbaum, Rafail Ostrovsky A Note On One-Prover, Instance-Hiding Zero-Knowledge Proof Systems. , In Proceedings of the first international symposium in cryptology in Asia (ASIACRYPT'91).
Rafail Ostrovsky One-way Functions, Hard on Average Problems and Statistical Zero-knowledge Proofs. , In Proceedings of 6th Annual Structure in Complexity Theory Conference (STRUCTURES-91) June 30 -- July 3, 1991, Chicago. pp. 51-59.
Mihir Bellare, Silvio Micali, Rafail Ostrovsky. Perfect Zero-Knowledge in Constant Rounds. , In Proceedings of 22nd annual ACM Symposium on Theory of Computing (STOC-90).
Mihir Bellare, Silvio Micali, and Rafail Ostrovsky The (True) Complexity of Statistical Zero Knowledge. , In Proceedings of 22nd annual ACM Symposium on Theory of Computing (STOC-90).
Joe Kilian, Silvio Micali, Rafail Ostrovsky Minimum Resource Zero-Knowledge Proofs. , In Proceedings of 30th annual IEEE Symposium on the Foundations of Computer Science (FOCS-89).

Digital Signatures, Passwords and Biometric Identification

Steve Lu, Rafail Ostrovsky, Amit Sahai, Hovav Shacham, and Brent Waters Sequential Aggregate Signatures and Multisignatures Without Random Oracles , In Proceedings of Advances in Eurocrypt, (EUROCRYPT-2006) Springer-Verlag/IACR Lecture Notes in Computer Science.
Xavier Boyen, Yevgeniy Dodis, Jonathan Katz, Rafail Ostrovsky, Adam Smith. Secure Authentication Using Biometric Data, In Proceedings of Advances in Eurocrypt, (EUROCRYPT-2005) Springer-Verlag/IACR Lecture Notes in Computer Science.
Jonathan Katz, Rafail Ostrovsky, Moti Yung Forward Security in Password-Only Key Exchange Protocols, In Proceedings of Security in Communication Networks 2002 conference (CSN-2002) Springer-Verlag Lecture Notes in Computer Science.
Jonathan Katz, Rafail Ostrovsky, Moti Yung Efficient Password-Authenticated Key Exchange Using Human-Memorable Passwords , In Proceedings of Advances in Cryptology, (EUROCRYPT-2001) Springer-Verlag/IACR Lecture Notes in Computer Science.
Ari Juels, Michael Luby, Rafail Ostrovsky Security of Blind Digital Signatures , In Proceedings of advances in cryptology, (CRYPTO-97) Springer-Verlag Lecture Notes in Computer Science.
Shafi Goldwasser, Rafail Ostrovsky Invariant Signatures and Non-Interactive Zero-Knowledge Proofs are Equivalent. , In Proceedings of Advances in Cryptology (CRYPTO-92) Springer-Verlag Lecture Notes in Computer Science.

Secure Two-Party and Multi-Party Computation

Jonathan Katz, Rafail Ostrovsky Round-Optimal Secure Two-Party Computation , In Proceedings of Advances in Cryptology, (CRYPTO-2004) Springer-Verlag/IACR Lecture Notes in Computer Science.
Jonathan Katz, Rafail Ostrovsky, Adam Smith Round Efficiency of Multi-Party Computation with a Dishonest Majority, In Proceedings of Advances in Eurocrypt, (EUROCRYPT-2003) Springer-Verlag/IACR Lecture Notes in Computer Science.
Ran Canetti, Yehuda Lindell, Rafail Ostrovsky, Amit Sahai Universally composable two-party and multi-party secure computation., In Proceedings of the ACM 2002 Symposium on Theory of Computing (STOC-2002).
Matthias Fitzi, Juan A. Garay, Ueli Maurer, Rafail Ostrovsky Minimal Complete Primitives for Secure Multi-Party Computation , Journal of Cryptology Springer-Verlag Volume 18, Number 1, January 2005 pp.37 - 61. Preliminary version in Proceedings of Advances in Cryptology, (CRYPTO-2001) Springer-Verlag/IACR Lecture Notes in Computer Science.
Ran Canetti, Rafail Ostrovsky Secure Computation with Honest-Looking Parties , In Proceedings of The 31'st ACM Symposium on Theory of Computing (STOC-99)
Eyal Kushilevitz, Rafail Ostrovsky, Adi Rosen Amortizing Randomness in Private Multiparty Computations , In Proceedings of Seventeenth Annual ACM Symposium on Principles of Distributed Computing (PODC-98).
Ran Canetti, Eyal Kushilevitz, Rafail Ostrovsky, Adi Rosen Randomness vs. Fault-Tolerance , In Proceedings of Sixteenth Annual ACM Symposium on Principles of Distributed Computing (PODC-97). Journal version in Journal of Cryptology 13(1): 107-142 (2000).
Eyal Kushilevitz, Rafail Ostrovsky, Adi Rosen Characterizing Linear Size Circuits in Terms of Privacy. , Invited paper to the Journal of Computer and System Sciences special issue for STOC 96. In Vol 58, JCSS 58(1): 129-136 (1999). Preliminary version appeared in the Proceedings of The Twenty-Eighth ACM Symposium on Theory of Computing (STOC-96).
Joe Kilian, Eyal Kushilevitz, Silvio Micali, Rafail Ostrovsky Reducibility and Completeness In Multi-Party Private Computations. , Preliminary version appeared in Proceedings of Thirty-fifth Annual IEEE Symposium on the Foundations of Computer Science (FOCS-94). Journal version in SIAM J. Comput. 29(4): 1189-1208 (2000).
Rafail Ostrovsky, Moti Yung. How to Withstand Mobile Virus Attacks. In Proceedings of 10th annual ACM Symposium on Principles of Distributed Computing (PODC-91).
Rafail Ostrovsky and Moti Yung. On Necessary Conditions for Secure Distributed Computation. , In DIMACS Series in Discrete Mathematics and Theoretical Computer Science, Volume 2. 1990. Proceedings of a DIMACS workshop, October 4-6, 1989, pp. 229-234.

Non-Malleable Commitment Protocols, and Commitments with special properties.

Giovanni Di Crescenzo, Jonathan Katz, Rafail Ostrovsky, Adam Smith Efficient and Non-interactive Non-malleable Commitment , In Proceedings of Advances in Cryptology, (EUROCRYPT-2001) Springer-Verlag/IACR Lecture Notes in Computer Science.
Rafail Ostrovsky, Charles Rackoff, Adam Smith Efficient Consistency Proofs for Generalized Queries on a Committed Database , In Proceedings ICALP-2004.
Giovanni Di Crescenzo, Yuval Ishai, Rafail Ostrovsky Non-Interactive and Non-Malleable Commitment , In Proceedings of The 30's ACM Symposium on Theory of Computing (STOC-98).
Moni Naor, Rafail Ostrovsky, Ramarathnam Venkatesan, Moti Yung. Perfect Zero-Knowledge Arguments for NP Can Be Based on General Complexity Assumptions. , Preliminary version in Proceedings of advances in cryptology (CRYPTO-92) Springer-Verlag Lecture Notes in Computer Science. Journal version in J. of Cryptology, 1988.
Rafail Ostrovsky, Ramarathnam Venkatesan, Moti Yung. Secure Commitment Against Powerful Adversary: A Security Primitive based on Average Intractability. , In Proceedings of 9th Symposium on Theoretical Aspects of Computer Science (STACS-92).
Rafail Ostrovsky, Ramarathnam Venkatesan, Moti Yung Fair Games Against an All-Powerful Adversary. , Initially presented at DIMACS workshop, 1990. Extended abstract in the proceedings of Sequences '91, June 1991, Positano, Italy. Journal version in AMS DIMACS Series in Discrete Mathematics and Theoretical Computer Science}. Vol 13. (Jin-Yi Cai ed.) pp. 155-169, 1993.

Cryptographically-Strong Hash Functions

Yuval Ishai, Eyal Kushilevitz, Rafail Ostrovsky Sufficient Conditions for Collision-Resistant Hashing, In Proceedings of Second Theory of Cryptography Conference (TCC-2005)Springer-Verlag Lecture Notes in Computer Science, 2005.

Issues of Anonymity

Yuval Isahi, Eyal Kushilevitz, Rafail Ostrovsky, Amit Sahai Cryptography from Anonymity, In Proceedings of 47st Annual IEEE Symposium on the Foundations of Computer Science (FOCS-2006).
Shlomi Dolev, Rafail Ostrovsky Efficient Anonymous Multicast and Reception ,
Preliminary version in proceedings of advances in cryptology, (CRYPTO-97) Springer-Verlag Lecture Notes in Computer Science. Journal version in ACM Trans. Inf. Syst. Secur. 3(2): 63-84 (2000)

PKI, Identity revocation and Public-Key Encryptions with Additional Properties

William Aiello, Sachin Lodha, Rafail Ostrovsky Fast Digital Identity Revocation , In Proceedings of advances in cryptology, (CRYPTO-98) Springer-Verlag Lecture Notes in Computer Science.
Ran Canetti, Cynthia Dwork, Moni Naor, Rafail Ostrovsky Deniable Encryption. , In Proceedings of advances in cryptology, (CRYPTO-97) Springer-Verlag Lecture Notes in Computer Science.

Cryptographic Applications: Electronic Voting, Micropayments, Time-release encryption, Conditional Oblivious Transfer

Jonathan Katz, Steven Myers, Rafail Ostrovsky Cryptographic Counters and Applications to Electronic Voting. , In Proceedings of Advances in Cryptology, (EUROCRYPT-2001) Springer-Verlag/IACR Lecture Notes in Computer Science.
Richard J. Lipton, Rafail Ostrovsky Micro-Payments via Efficient Coin-Flipping , In Proceedings of Second Financial Cryptography Conference, (FINANCIAL CRYPTO-98) February 1998. Lecture Notes in Computer Science LNCS volume 1465
Giovanni Di Crescenzo, Rafail Ostrovsky, S. Rajagopalan Efficient Timed-release Public-key Encryption , In Proceedings of EUROCRYPT-99 Springer Verlag.

Publications: Geometric Search and Analysis of High-Dimensional Data

Dimension Reduction, Emeddings and Geometric search

Rafail Ostrovsky, Yuval Rabani. Low distortion embedding for edit distance, Preliminary version appeared in STOC '05.
Allan Borodin, Rafail Ostrovsky, Yuval Rabani Lower Bounds for High Dimensional Nearest Neighbor Search and Related Problems , Book Chapter In Discrete and Computational Geometry - The Goodman-Pollack Festschrift. Algorithms and Combinatorics Series 3143, Springer Verlag, Berlin, August 2003, pages 252-274. Preliminary version appeared in STOC '99.
Eyal Kushilevitz, Rafail Ostrovsky, Yuval Rabani Efficient Search for Approximate Nearest Neighbor in High Dimensional Spaces , SIAM J. Comput. 30(2): 457-474 (2000). Preliminary version in Proceedings of The 30's ACM Symposium on Theory of Computing (STOC-98)

Clustering Algorithms for high-dimensional data

Rafail Ostrovsky, Yuval Rabani, Leonard Schulman, and Chaitanya Swamy The Effectiveness of Lloyd-Type Methods for the k-Means Problem. In Proceedings of 47st Annual IEEE Symposium on the Foundations of Computer Science (FOCS-2006).
Rafail Ostrovsky, Yuval Rabani. Polynomial Time Approximation Schemes for Geometric k-Clustering. , In Proceedings of 41st Annual IEEE Symposium on the Foundations of Computer Science (FOCS-2000). Journal version in JACM 49(2): 139-156 (2002).
Allan Borodin, Rafail Ostrovsky, Yuval Rabani Subquadratic Approximation Algorithms For Clustering Problems in High Dimensional Spaces , Preliminary version in proceedings of The 31'st ACM Symposium on Theory of Computing (STOC-99), Journal version in Machine Learning Journal Special Issue: Theoretical Advances in Data Clustering 56 (1-3): 153-167, 2004.

Publications: Distributed Control Theory, Network Algorithms and Combinatorial Algorithms

Admission Control and Network Routing Algorithms

William Aiello, Rafail Ostrovsky, Eyal Kushilevitz, Adi Rosen Dynamic Routing on Networks with Fixed-Sized Buffers, In Proceedings of 2003 SIAM Symposium on Discrete Algorithms (SODA-2003).
Allan Borodin, Rafail Ostrovsky, Yuval Rabani. Stability Preserving Transformations: Packet Routing Networks with Edge Capacities and Speeds , In Proceedings of the Twelfth Annual ACM-SIAM Symposium on Discrete Algorithms (SODA-2001). Journal version in Journal of Interconnection Networks, Vol. 5, No. 1, pp. 1-12.
William Aiello, Eyal Kushilevitz, Rafail Ostrovsky, Adi Rosen Adaptive Packet Routing for Bursty Adversarial Traffic , In Proceedings of The 30's ACM Symposium on Theory of Computing (STOC-98). Journal version appeared in JCSS 60(3): 482-509 (2000).
Rafail Ostrovsky, Yuval Rabani Universal O(congestion+dilation+log(N)) Local Control Packet Switching Algorithm , In Proceedings of The Twenty-Ninth ACM Symposium on Theory of Computing (STOC-97).
Eyal Kushilevitz, Nati Linial, Rafail Ostrovsky The Linear-Array Conjecture in Communication Complexity is False. , Preliminary version in Proceedings of The Twenty-Eighth ACM Symposium on Theory of Computing (STOC-96) Journal version in Combinatorica 19(2): 241-254 (1999)

Distributed Algorithms with severely limited memory per processor

Alain Mayer, Rafail Ostrovsky, Moti Yung Self-Stabilizing Algorithms for Synchronous Unidirectional Rings. , In Proceedings of Seventh Annual ACM-SIAM Symposium on Discrete Algorithms (SODA-96) January 28-30, Atlanta, Georgia.
Rafail Ostrovsky, Wilkersan Faster Computation On Directed Networks of Automata , In the Proceedings of Fourteenth Annual ACM Symposium on Principles of Distributed Computing (PODC-95).
Eyal Kushilevitz, Rafail Ostrovsky, Adi Rosen LOG-Space Polynomial End-to-End Communication , In SIAM Journal of Computing Volume 27, 1998. SIAM J. Comput. 27(6): 1531-1549 (1998). Preliminary version appeared in the Proceedings of Twenty-seventh ACM Symposium on Theory of Computing STOC-95.
Baruch Awerbuch, Rafail Ostrovsky Memory-Efficient and Self-Stabilizing Network RESET. , In Proceedings of Thirteens Annual ACM Symposium on Principles of Distributed Computing (PODC-94),

Symmetry Breaking

Rafail Ostrovsky, Sridhar Rajagopalan, Umesh Vazirani Simple and Efficient Leader Election In The Full Information Model. , In Proceedings of Twenty-sixth ACM Symposium on Theory of Computing (STOC-94).
Shay Kutten, Rafail Ostrovsky, Boaz Patt-Shamir. The Las-Vegas Processor Identity Problem , In Proceedings of the Second Israel Symposium on Theory of Computing and Systems (ISTCS-93) Journal version appeared in J. Algorithms 37(2): 468-494 (2000).
Alain Mayer, Yoram Ofek, Rafail Ostrovsky, Moti Yung Self-Stabilizing Symmetry Breaking in Constant-Space. , In Proceedings of 24th annual ACM Symposium on Theory of Computing (STOC-92).

Distributed Control Theory and Error-Correcting Codes

Rafail Ostrovsky, Yuval Rabani, Leonard Schulman. Error-Correcting Codes for Automatic Control, In Proceedings of 46th Annual IEEE Symposium on the Foundations of Computer Science (FOCS-2005).
Yuval Isahi, Eyal Kushilevitz, Rafail Ostrovsky, Amit Sahai Batch Codes and Their Applications, In Proceedings of the ACM 2004 Symposium on Theory of Computing (STOC-2004).

Clock synchronization in distributed networks

Rafail Ostrovsky, Boaz Patt-Shamir Optimal and Efficient Clock Synchronization Under Drifting Clocks , In Proceedings of Eighteenth Annual ACM Symposium on Principles of Distributed Computing (PODC-99).

Combinatorial Algorithms

Julia Chuzhoy, Rafail Ostrovsky, Yuval Rabani. Approximation Algorithms for the Job Interval Selection Problem and Related Scheduling Problems. Preliminary version in (FOCS-2001). Journal version accepted to Journal of Mathematics of Operations Research.
Noga Alon, Manuel Blum, Amos Fiat, Sampath K. Kannan, Moni Naor, Rafail Ostrovsky Matching Nuts and Bolts. , In Proceedings of the Fifth Annual ACM-SIAM Symposium on Discrete Algorithms (SODA-94),

Some Past and Present Professional Activities

Chair, Institute of Pure and Applied Mathematics semester-long program dedicated to Cybersecurity. September - December, 2006.
Editorial Board member Algorithmica 2005--.
Steering Committee member Conference on Security and Cryptography for Networks 2005--.
Editorial and Advisory Board member International Journal of Information and Computer Security. 2004--.
Co-chair, Dagshtul Workshop Anonymous Communication and its Applications October 9-14, 2005.
Co-organizer, IPAM Workshop Multiscale Geometry and Analysis in High Dimensions October 19-23, 2004.
Co-organizer, DIMACS Workshop Cryptographic Protocols in Complex Environments May 15-17, 2002.
Program committee member ACISP-2007 12th Australian Conference on Information Security and Privacy July 2-6, 2007, Townsville, Queensland, Australia.
Program committee member PKC-2007: International Workshop on Practice and Theory in Public Key Cryptography, (Apr 17-19 2007, Beijing). China 2007
Program committee member ICALP-2006: 33rd International Colloquium on Automata, Languages and Programming, July 9-16, 2006, Venice, Italy
Program committee member STOC-2006: Annual ACM Symposium on Theory of Computing, May 2006.
Program committee member PKC 2006: International Workshop on Practice and Theory in Public Key Cryptography, April 24-26, New York City, USA.
Program committee member INDOCRYPT-2005 December 10-12, 2005 Indian Institute of Science Bangalore, India, 2005.
Program committee member EUROCRYPT-2005 Aarhus, May 22-26, 2005.
Program committee member TCC-2005: Second Theory of Cryptography Conference, Feb 2005.
Program committee member SCN-2004 Security in Communication Networks 2004 to be held on September 8-10 in Amalfi, Italy.
Program committee member PODC-2004: 23rd Annual ACM Symposium on Principles of Distributed Computing, July 2004.
Program committee member CRYPTO-2004: 24nd Annual IACR/IEEE Conference on Cryptologic Research, August 2004.
Program committee member CRYPTO-2003: 23nd Annual IACR/IEEE Conference on Cryptologic Research, August 2003.
Program committee member STOC-2003: Annual ACM Symposium on Theory of Computing, May 2003.
Program committee member CRYPTO-2002: 22nd Annual IACR/IEEE Conference on Cryptologic Research, 2002.
Program committee member RANDOM-2002: The 6th International Workshop on Randomization and Approximation Techniques in Computer Science, 2002.
Program committee member SCN-2002: Third Workshop on Security in Communication Networks, September 2002, Amalfi, Italy.
Program committee member STOC-2000: Annual ACM Symposium on Theory of Computing, 2000.
Program committee member SODA-2000: Eleventh Annual ACM-SIAM Symposium on Discrete Algorithms, , January 1-9, 2000, San Francisco.
Program committee member SCN-99: Second Workshop on Security in Communication Networks, September 1999, Italy.
Program committee member CRYPTO-98: 18th Annual IACR/IEEE Conference on Cryptologic Research 1998.
Program committee member ISTCS-97: 5th ISRAEL Symposium on Theory of Computing and Systems, 1997.

Invited Talks (from September 2005):

Invited talk: Sun Microsystems, 2007 Distinguished Lecture Series, January 2007, Palo Alto, CA, USA
Invited tutorial: Series of IPAM lectures on Private Information Retrieval September 2006, Los Angeles, CA, USA.
Two invited talks at Homeland Defense and Security Conference 18-21 Octover 2006, Sorrento, Italy.
Invited talk: 2006 Xerox Corporation Distinguished Lecture Series Los Angeles, July 2006. USA
Invited talk: Workshop on Data Surveillance and Privacy Protection Harvard University's Center for Research on Computation and Society, June 3rd, 2006. Harvard, USA
Invited talk: Workshop on classical & quantum information security Caltech, December 15-18, 2005.
Invited talk: Interdepartmental Seminar on Algorithmics University of Rome "La Sapienza", Italy. November 21, 2005.
Invited talk: 2005 Distinguished Cryptographer Lecture Series NTT Labs, Kanagawa, Japan, October 2005.
Invited talk: Workshop on Cryptography and Information Security 2005 Tokyo, Japan, October 21, 2005.
Invited talk: IEEE Information Theory Workshop on Theory and Practice in Information-Theoretic Security Awaji Island, Japan, October 16- 19, 2005.
Invited talk: Dagshtul Workshop. Germany, October 9-14, 2005.
Invited talk: Southern California Security and Cryptography Workshop September 24, 2005, Irvine, CA. USA
Invited talk: Bertinoro Invited one-week course, International PhD School on Mathematical Aspects of Modern Cryptography, Bertinoro, Italy September 4-9, 2005.

* Contact info * Bio * Teaching * Interested in working with me? * In popular press *

Photos:

My favorite poems.