Publica
Hier finden Sie wissenschaftliche Publikationen aus den FraunhoferInstituten. On constructing homomorphic encryption schemes from coding theory
 Chen, L.: Cryptography and coding. 13th IMA international conference, IMACC 2011 : Oxford, UK, December 12  15, 2011 Berlin: Springer, 2011 (Lecture Notes in Computer Science 7089) ISBN: 9783642255168 ISBN: 3642255159 (print) ISSN: 03029743 pp.2340 
 IMA International Conference on Cryptography and Coding (IMACC) <13, 2011, Oxford> 

 English 
 Conference Paper 
 Fraunhofer SIT () 
Abstract
We introduce a generic construction principle for homomorphic encryption schemes based on coding theory These possess several nonstandard positive features. First, they are not restricted to linear homomorphism but allow for evaluating multivariate polynomials up to a fixed (but arbitrary) degree on encrypted field elements. Second, they can be instantiated with various error correcting codes, even for codes with poor correcting capabilities. Third, depending on the deployed code, one can achieve very efficient schemes. As a concrete example, we present an instantiation based on ReedMuller codes where for = 2 and = 3 and security levels between 80 and 128 bits, all operations take less than a second (after some precomputation). However, our analysis reveals also limitations on this approach. For structural reasons, such schemes cannot be publickey, allow for a limited number of fresh encryptions only, and cannot be combined with the bootstrapping technique. We ar gue why such schemes are nonetheless useful in certain application scenarios and discuss possible directions on how to overcome these issues.