In particular, we provide the first treeless signature scheme that supports strong unforgeability for the post-quantum era in the standard model.
Moreover, we show how to directly implement identity-based, and even hierarchical identity-based, signatures (IBS) in the same strong security model without random oracles. An additional advantage of this direct approach over the usual generic conversion of hierarchical identity-based encryption to IBS is that we can exploit the efficiency of ideal lattices without significantly harming security.
We equip all constructions with strong security proofs based on mild worst-case assumptions on lattices and we also propose concrete security parameters.Category / Keywords: public-key cryptography / Post-quantum cryptography, lattice cryptography, digital signatures, identity-based cryptography, standard model Publication Info: PQCrypto 2010 Date: received 10 Feb 2010, last revised 1 Mar 2010 Contact author: rueckert at cdc informatik tu-darmstadt de Available format(s): PDF | BibTeX Citation Note: Full version. Version: 20100301:091923 (All versions of this report) Short URL: ia.cr/2010/070 Discussion forum: Show discussion | Start new discussion