To this end, we introduce a novel LWE-close assumption, namely Augmented Learning with Errors (A-LWE), which allows to hide auxiliary data injected into the error term by a technique that we call message embedding. In particular, it enables existing cryptosystems to strongly increase the message throughput per ciphertext. We show that A-LWE is for certain instantiations at least as hard as the LWE problem. This inherently leads to new cryptographic constructions providing high data load encryption and customized security properties as required, for instance, in economic environments such as stock markets resp. for financial transactions. The security of those constructions basically stems from the hardness to solve the A-LWE problem.
As an application we introduce (among others) the first lattice-based replayable chosen-ciphertext secure encryption scheme from A-LWE.Category / Keywords: public-key cryptography / Lattice-Based Cryptography, Encryption Scheme, Lattice-Based Assumptions Original Publication (in the same form): Financial Cryptography and Data Security 2015 Date: received 19 Sep 2014, last revised 26 Feb 2017 Contact author: elbansarkhani at cdc informatik tu-darmstadt de Available format(s): PDF | BibTeX Citation Note: Only acknowledgements added. Version: 20170226:142325 (All versions of this report) Short URL: ia.cr/2014/733 Discussion forum: Show discussion | Start new discussion