Efficient attributes in secure credentials

We propose a new method to efficiently encode attributes in the Camenisch-Lysyanskaya anonymous credential system. The new method is based on the Chinese remainder theorem. We show that with this method all attributes, including integer and string based attributes can be efficiently encoded. Also, we show that the number of bits needed for encoding attributes could be decreased by up to 48%. The protocols for finite-set attributes have the same complexity level as the work by Camenisch and Groß, but for string and integer based attributes, we decrease the complexity from O(l) to O(1).