Research Fellow, University of Tartu, Estonia
Coding and Cryptography Group at the University of Tartu, Estonia, is looking for a research fellow for a project on design and decoding of LDPC codes. The ideal candidate will have strength in one or more of the following areas:
• LDPC codes and iterative decoding algorithms
• Optimization methods applied to error correction
• Mathematical foundations of coding theory
• Any area related to coding theory
The project is a collaboration with the University of Bergen, Norway, and the University of Valladolid, Spain. Salary is at least 2000 euro per month before taxes plus social benefits, depending on qualification and experience. Some travel money will also be provided. Cost of living in Estonia is quite low, see e.g. http://www.expatistan.com/cost-of-living. Employment contract is for two years.
A successful candidate should:
• Hold a Ph.D. degree
• Have a strong background in coding theory or a related field
• Have an international publication record at outstanding venues
To apply, please submit the following documents (by email):
• Application letter
• Research statement
• Curriculum vitae
• Publication list
• Document about academic degree, if available
• Two letters of reference (make sure they reach us by the application deadline)
Deadline for applications: 1 February 2014
Do not hesitate to contact us in case of questions.
Fully funded Ph.D., Ecole normale supérieure (Paris Area, France)
The objective of this thesis is the forensic reconstruction of partially erased data of various types. The problem that we will tackle is formalized as follows: We consider a data object instance as the result of a function F(t,r) where t encodes the objet type and r is a random number. The OS can create objects, erase them or update them. Erasure is done by forgetting the object’s reference and hence implicitly recycling the space on which it was written. The problem consists in reconstructing algorithmically erased data objects of various types and modeling the conditions under which various assortments of types subject to a given number of rewriting cycles can still be recovered. The methods that will be developed will subsequently be applied to iOS and Android.
The candidate should have solid programming and algorithmic skills. Prior knowledge of reverse engineering tools such as IDA Pro is a plus. The candidate will interact with zero-day exploit hunters and physical reverse engineering experts and will have access to very advanced computing and forensic facilities. This proposal is reserved to French nationals only and is fully funded.
Interested candidates should contact directly david.naccache (at) ens.fr
Tightly-Secure Signatures From Lossy Identification Schemes, by Michel Abdalla and Pierre-Alain Fouque and Vadim Lyubashevsky and Mehdi Tibouchi
In this paper we present three digital signature schemes with tight security reductions. Our first signature scheme is a particularly efficient version of the short exponent discrete log based scheme of Girault et al. (J. of Cryptology 2006). Our scheme has a tight reduction to the decisional Short Discrete Logarithm problem, while still maintaining the non-tight reduction to the computational version of the problem upon which the original scheme of Girault et al. is based. The second signature scheme we construct is a modification of the scheme of Lyubashevsky (Asiacrypt 2009) that is based on the worst-case hardness of the shortest vector problem in ideal lattices. And the third scheme is a very simple signature scheme that is based directly on the hardness of the Subset Sum problem.
We also present a general transformation that converts what we term lossy identification schemes into signature schemes with tight security reductions. We believe that this greatly simplifies the task of constructing and proving the security of
such signature schemes.
Post-Doc, EPFL, Switzerland
The Laboratory for Security and Cryptography (LASEC) at EPFL is hiring a post doctoral researcher. Applicants are encouraged to apply to job_lasec (at) epfl.ch by sending a detailed CV and a research plan.
LASEC is active in research on cryptography and security. More specifically, our main interests currently span (but are not limited to) the following:
- hardware implementation and embedded systems,
- homomorphic and functional encryption,
- provable security.
We strongly encourage the application by researchers who have proved
excellence in one of these domains.
The selection of applicants will be made on a competitive basis.
Besides conducting top-quality research, postdocs are required to
participate the the lab activities such as training students at all levels,
running projects, fund raising, etc.
EPFL is a top-ranked research and teaching institution that attracts
some of the best intellects in the world. EPFL offers excellent
facilities, environment, and salaries. EPFL\\\'s campus is a multi
cultural, idyllic spot overlooking Lake Geneva and facing the Alps.
Information about EPFL: http://www.epfl.ch
A generic view on trace-and-revoke broadcast encryption schemes, by Dennis Hofheinz and Christoph Striecks
At Eurocrypt 2011, Wee presented a generalization of threshold public key encryption, threshold signatures, and revocation schemes arising from threshold extractable hash proof systems. In particular, he gave instances of his generic revocation scheme from the DDH assumption (which led to the Naor-Pinkas revocation scheme), and from the factoring assumption (which led to a new revocation scheme). We expand on Wee\'s work in two directions:
(a) We propose threshold extractable hash proof instantiations from the \"Extended Decisional Diffie-Hellman\" (EDDH) assumption due to Hemenway and Ostrovsky (PKC 2012). This in particular yields EDDH-based variants of threshold public key encryption, threshold signatures, and revocation schemes. In detail, this yields a DCR-based revocation scheme.
(b) We show that our EDDH-based revocation scheme allows for a mild form of traitor tracing (and, thus, yields a new trace-and-revoke scheme). In particular, compared to Wee\'s factoring-based scheme, our DCR-based scheme has the advantage that it allows to trace traitors.