Call for IACR Cryptology School Proposals
In 2014, IACR started to sponsor a small number of Cryptology Schools providing intensive training on clearly identified topics in cryptology. The aim of this program is to develop awareness and increased capacity for research in cryptology.
A Cryptology School is typically held full-time for 4-5 days of intensive learning and constitutes an efficient way to provide high-quality training for graduate students, as well as for professionals. Attendance should be open to anyone who is interested and qualified. In order to facilitate learning, a school is usually taught by a few domain experts with a focus on educating the audience rather than impressing with results. In line with the mission of IACR, a Cryptology School should enable the audience to advance the theory and practice of cryptology and related fields.
There are two rounds of submissions every year. The submission deadlines are:
Submissions must be sent by email to firstname.lastname@example.org.
- December 31st of year X-1: For schools that take place between March of year X and February of year X + 1.
- June 30th of year X: For schools that take place between September of year X and August of year X + 1.
For more information about this new program and how to prepare a proposal, please refer to http://www.iacr.org/schools/
Incentivized Outsourced Computation Resistant to Malicious Contractors, by Alptekin Kupcu
With the rise of Internet computing, outsourcing difficult computational tasks became an important need. Yet, once the computation is outsourced, the job owner loses control, and hence it is crucial to provide guarantees against malicious actions of the contractors involved. Cryptographers have an almost perfect solution, called fully homomorphic encryption, to this problem. This solution hides both the job itself and any inputs to it from the contractors, while still enabling them to perform the necessary computation over the encrypted data. This is a very strong security guarantee, but the current constructions are highly impractical.
In this paper, we propose a different approach to outsourcing computational tasks. We are not concerned with hiding the job or the data, but our main task is to ensure that the job is computed correctly. We also observe that not all contractors are malicious; rather, majority are rational. Thus, our approach brings together elements from cryptography, as well as game theory and mechanism design. We achieve the following results: (1) We incentivize all the rational contractors to perform the outsourced job correctly, (2) we guarantee high fraction (e.g., 99.9%) of correct results even in the existence of a relatively large fraction (e.g., 33%) of malicious irrational contractors in the system, (3) and we show that our system achieves these while being almost as efficient as running the job locally (e.g., with only 3% overhead). Such a high correctness guarantee was not known to be achieved with such efficiency.
Two novel applications of bilinear groups to ABE encryption, by Riccardo Longo and Chiara Marcolla and Massimiliano Sala
Bilinear groups are often used to create Attribute-Based Encryption (ABE) algorithms.
In particular, they have been used to create an ABE system with multi authorities, but limited to the ciphertext-policy instance.
Here, for the first time, we propose two multi-authority key-policy ABE systems.
In our first proposal, the authorities may be set up in any moment and without any coordination.
A party can simply act as an ABE authority by creating its own public parameters and issuing private keys to the users.
A user can thus encrypt data choosing both a set of attributes and a set of trusted authorities, maintaining full control unless all his chosen authorities collude against him.
In our second system, the authorities are allowed to collaborate to achieve shorter keys and parameters, enhancing the efficiency of encryption and decryption.
We prove our systems secure under algebraic assumptions on the bilinear groups: the bilinear Diffie-Hellmann assumption and an original variation of the former.