Paulo Barreto, Ph.D.

Assistant Professor
Campus Box
Current Research

My research interests in cryptography are completely eclectic. All individual research targets (from the most theoretical to the essentially practical) are anchored in real-world needs.

This includes (but is not restricted to) the following topics, all of which are represented one or more times among my published and submitted papers:

  • Design and analysis of block ciphers, modes of operation for block ciphers, and hash functions
  • Cryptography sponges and password derivation schemes
  • Efficient algorithms for pairing-based cryptosystems
  • Identity-based key agreement schemes, digital signatures and signcryption from bilinear pairings
  • Construction of pairing-friendly elliptic curves
  • Efficient and side-channel-resistant implementation of pairings and elliptic curve cryptography
  • Code-based encryption
  • Hash-based digital signatures
  • Lattice-based and homomorphic cryptosystems



My teaching experience extends from the early 2000’s to the present, although occasional teaching activities could be traced back to the early 1990’s. Over the past 10 years, I have been teaching the following courses at the University of São Paulo:

  • Elliptic Curve & Pairing-Based Cryptography (grad level)
  • Post-Quantum Cryptography (grad level)
  • Quantum Cryptography (grad level)
  • Network & Information Security (grad level)
  • Information Security (undergrade level)
  • Computer Systems Performance Evaluation (60 hours, undergrad level)
  • Computer Networks (undergrad level)
  • Advanced Algorithms (grad level)
  • Design and Anaylsis of Algorithms (undergrad level)
  • Compiler Construction (undergrad level)
  • Undergraduate Seminar in CSS (undergrad level)

I am also a member of the MSc in Computer Science program committee at the Institute of Technology of the University of Washington Tacoma. In this context, I am working to create the new course on Post-Quantum Cryptography (to be offered for the first time in 2016). I am also collaborating with the researchers of the Center for Data Science of the University of Washington Tacoma along the research area of Secure Machine Learning.

CV or Resume
Publication Date Bibliographic Citation

Andrade, E.; Simplicio Jr., M.; BARRETO, P. S. L. M.; Santos, P.: “Lyra2: efficient password hashing with high security against time-memory trade-offs.” IEEE Transactions on Computers, 2016, to appear. DOI: 10.1109/TC.2016.2516011.


Possignolo, R. T.; Margi, C. B.; BARRETO, P. S. L. M.: “Quantum-assisted QDCFS signatures.” Journal of Computer and System Sciences, v. 81, p. 458-467, 2015.


Barguil, J. M. M.; BARRETO, P. S. L. M.: “Security issues in Sarkar’s e-cash protocol.” Information Processing Letters, v. 115, n. 11, p. 801-803, 2015.


Massolino, P. M. C.; BARRETO, P. S. L. M.; Ruggiero, W. V.: “Optimized and Scalable Co-Processor for McEliece with Binary Goppa Codes.” ACM Transactions on Embedded Computing Systems, v. 14, p. 1-32, 2015.


Pereira, G. C. C. F.; Puodzius, C. O.; BARRETO, P. S. L. M.: “Shorter HashBased Signatures.” The Journal of Systems and Software, 2015, v. 116, p. 95-100.


Almeida, L. C.; Andrade, E. R.; BARRETO, P. S. L. M.; Simplicio Jr., M. A.: “LYRA: password-based key derivation with tunable memory and processing costs.” Journal of Cryptographic Engineering, v. 4, n. 2, p. 75-89, 2014.