A lattice-based batch identification scheme

This paper presents a batch version of the lattice-based identification scheme known as CLRS. Our version consists of a method for allowing a user to authenticate himself with different levels of clearance upon the choice of a subset of keys in his possession. It bears similarity with the Schnorr batch scheme, in the sense that the communication costs are kept constant, regardless of the number of keys involved. We use the hardness of a lattice problem, namely the Inhomogeneous Small Integer Solution problem (I-SIS), as security assumption.