How to Construct Quantum Random Functions, by Mark Zhandry
In the presence of a quantum adversary, there are two possible definitions of security for a pseudorandom function. The first, which we call standard-security, allows the adversary to be quantum, but requires queries to the function to be classical. The second, quantum-security, allows the adversary to query the function on a quantum superposition of inputs, thereby giving the adversary a superposition of the values of the function at many inputs at once. Existing proof techniques for proving the security of pseudorandom functions fail when the adversary can make quantum queries. We give the first quantum-security proofs for pseudorandom functions by showing that some classical constructions of pseudorandom functions are quantum-secure. Namely, we show that the standard constructions of pseudorandom functions from pseudorandom generators or pseudorandom synthesizers are secure, even when the adversary can make quantum queries. We also show that a direct construction from lattices is quantum-secure. To prove security, we develop new new tools to prove the indistinguishability of distributions under quantum queries.
In light of these positive results, one might hope that all standard-secure pseudorandom functions are quantum-secure. To the contrary, we show a separation - there exist pseudorandom functions secure against adversaries with only classical access to the function, but insecure once the adversary can make quantum queries.
Asymptotic fingerprinting capacity in the Combined Digit Model, by Dion Boesten and Boris Skoric
We study the channel capacity of $q$-ary ﬁngerprinting in the limit of large attacker coalitions.
We extend known results by considering the Combined Digit Model, an attacker model that captures signal processing attacks such as averaging and noise addition.
For $q=2$ we give results for various attack parameter settings.
For $q \\geq 3$ we present the relevant equations without providing a solution.
We show how the channel capacity in the Restricted Digit Model
is obtained as a limiting case of the Combined Digit Model.
Web-Site Update of the IACR
The IACR website has a new look. A team of cryptologists has recently started an effort to advance the online services of the IACR, and has formed a new online content team for this task. What you see today is the result of the first two months of steady improvements. We hope that you like it and that you find the new organization useful.
This is only a start, and we know that many things are not yet as integrated as we would wish. We are working on improving the site and you should visit http://www.iacr.org often to see further improvements.
Please send your feedback, praise, or bug reports to webbugs(at)iacr.org.
The online content core team:
Christian Cachin, Kevin McCurley, Nigel Smart, Christopher Wolf.
The online content extended team:
Shai Halevi, Hilarie Orman, Bart Preneel, abhi shelat.
Senior Lecturer of Theoretical Computer Science, University of Tartu, Estonia
We are seeking a candidate for the position of Senior Lecturer in Theoretical Computer Science (including cryptography).
A successful candidate will have extensive university-level teaching experience and didactic skills, experience in academic supervision of graduate students, as well as experience in research and a strong international publication track record.
The candidate will be able to teach courses in the area of theoretical computer science on Master level and advanced Bachelor level, in particular a course on discrete mathematics.
We are interested both in candidates who can contribute to existing research groups (cryptography, semantics) as well as in candidates who bring in new areas of research expertise.
Furthermore, the senior lecturer is expected to supervise Master and Ph.D. students.
For applying, please follow the instructions here: http://www.ut.ee/en/application-documents-and-notification-results and send you application to personal (at) ut.ee.