17 research outputs found
Transcript secure signatures based on modular lattices
We introduce a class of lattice-based digital signature schemes
based on modular properties of the coordinates of lattice vectors. We also
suggest a method of making such schemes transcript secure via a rejection
sampling technique of Lyubashevsky (2009). A particular instantiation
of this approach is given, using NTRU lattices. Although the scheme is
not supported by a formal security reduction, we present arguments for
its security and derive concrete parameters (first version) based on the
performance of state-of-the-art lattice reduction and enumeration tech-
niques. In the revision, we re-evaluate the security of first version of the
parameter sets, under the hybrid approach of lattice reduction attack
the meet-in-the-middle attack. We present new sets of parameters that
are robust against this attack, as well as all previous known attacks
Choosing Parameters for NTRUEncrypt
We describe a methods for generating parameter sets and calculating security estimates for NTRUEncrypt. Analyses are provided for the standardized product-form parameter sets from IEEE 1363.1-2008 and for the NTRU Challenge parameter sets
DA-Encrypt: Homomorphic Encryption via Non-Archimedean Diophantine Approximation --- Preliminary Report
We give a theoretical description of a new homomorphic encryption scheme DA-Encrypt that is based on (non-archimedean) Diophantine Approximation