Flexible Group Key Exchange with On-demand Computation of Subgroup Keys Supporting Subgroup Key Randomization

Keita Emura, Takashi Sato

Abstract

In AFRICACRYPT2010, Abdalla, Chevalier, Manulis, and Pointcheval proposed an improvement of group key exchange (GKE), denoted by GKE+S, which enables on-demand derivation of independent secret subgroup key for all potential subsets. On-demand derivation is efficient (actually, it requires only one round) compared with GKE for subgroup (which requires two or more rounds, usually) by re-using values which was used for the initial GKE session for superior group. In this paper, we improve the Abdalla et al. GKE+S protocol to support key randomization. In our GKE+S protocol, the subgroup key derivation algorithm is probabilistic, whereas it is deterministic in the original Abdalla et al. GKE+S protocol. All subgroup member can compute the new subgroup key (e.g., for countermeasure of subgroup key leakage) with just one-round additional complexity. Our subgroup key establishment methodology is inspired by the “essential idea” of the NAXOS technique. Our GKE+S protocol is authenticated key exchange (AKE) secure under the Gap Diffie-Hellman assumption in the random oracle model.

References

  1. Abdalla, M., Chevalier, C., Manulis, M., and Pointcheval, D. (2010). Flexible group key exchange with on-demand computation of subgroup keys. In AFRICACRYPT, pages 351-368.
  2. Boyd, C. and Nieto, J. M. G. (2003). Round-optimal contributory conference key agreement. In Public Key Cryptography, pages 161-174.
  3. Burmester, M. and Desmedt, Y. (1994). A secure and efficient conference key distribution system (extended abstract). In EUROCRYPT, pages 275-286.
  4. Cheng, Q. and Ma, C. (2010). Security weakness of flexible group key exchange with on-demand computation of subgroup keys. CoRR, abs/1008.1221.
  5. Gorantla, M. C., Boyd, C., Nieto, J. M. G., and Manulis, M. (2009). Generic one round group key exchange in the standard model. In ICISC, pages 1-15.
  6. Hatano, T., Miyaji, A., and Sato, T. (2011). T-robust scalable group key exchange protocol with O(logn) complexity. In ACISP, pages 189-207.
  7. Jarecki, S., Kim, J., and Tsudik, G. (2007). Robust group key agreement using short broadcasts. In ACM Conference on Computer and Communications Security, pages 411-420.
  8. Katz, J. and Shin, J. S. (2005). Modeling insider attacks on group key-exchange protocols. In ACM Conference on Computer and Communications Security, pages 180- 189. ACM.
  9. LaMacchia, B. A., Lauter, K., and Mityagin, A. (2007). Stronger security of authenticated key exchange. In ProvSec, pages 1-16.
  10. Wu, Q., Qin, B., Zhang, L., Domingo-Ferrer, J., and Farràs, O. (2011). Bridging broadcast encryption and group key agreement. In ASIACRYPT, pages 143-160.
Download


Paper Citation


in Harvard Style

Emura K. and Sato T. (2012). Flexible Group Key Exchange with On-demand Computation of Subgroup Keys Supporting Subgroup Key Randomization . In Proceedings of the International Conference on Security and Cryptography - Volume 1: SECRYPT, (ICETE 2012) ISBN 978-989-8565-24-2, pages 353-357. DOI: 10.5220/0003986003530357


in Bibtex Style

@conference{secrypt12,
author={Keita Emura and Takashi Sato},
title={Flexible Group Key Exchange with On-demand Computation of Subgroup Keys Supporting Subgroup Key Randomization},
booktitle={Proceedings of the International Conference on Security and Cryptography - Volume 1: SECRYPT, (ICETE 2012)},
year={2012},
pages={353-357},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0003986003530357},
isbn={978-989-8565-24-2},
}


in EndNote Style

TY - CONF
JO - Proceedings of the International Conference on Security and Cryptography - Volume 1: SECRYPT, (ICETE 2012)
TI - Flexible Group Key Exchange with On-demand Computation of Subgroup Keys Supporting Subgroup Key Randomization
SN - 978-989-8565-24-2
AU - Emura K.
AU - Sato T.
PY - 2012
SP - 353
EP - 357
DO - 10.5220/0003986003530357