Special Issue Paper
Improved group key transfer protocols from the protocol of Harn et al.
Article first published online: 6 FEB 2012
Copyright © 2012 John Wiley & Sons, Ltd.
Security and Communication Networks
Volume 6, Issue 12, pages 1471–1477, December 2013
How to Cite
Wang, Z. (2013), Improved group key transfer protocols from the protocol of Harn et al. Security Comm. Networks, 6: 1471–1477. doi: 10.1002/sec.415
- Issue published online: 28 NOV 2013
- Article first published online: 6 FEB 2012
- Manuscript Accepted: 5 NOV 2011
- Manuscript Revised: 31 AUG 2011
- Manuscript Received: 16 JUN 2011
- Priority Academic Program Development. Grant Number: 11KJB520015
- National Natural Science Foundation. Grant Numbers: 61073188, 60973046
- China Postdoctoral Science Foundation. Grant Number: 20100471355
- Program for Excellent Talents. Grant Number: NY209014
- group key transfer protocol;
- secret sharing;
- Lagrange interpolating polynomial;
- untrustworthy KGC;
- large group
In 2010, Harn et al. proposed an authenticated group key transfer protocol-based secret sharing. In their protocol, for distributing a secret group key involving t group members, the key generation center (KGC) needs to broadcast a message containing (t + 1) elements to all group members, whereas each group member needs to compute a tth-degree interpolating polynomial to recover the secret group key. Thus, the protocol of Harn et al. is only suitable for small-size groups. We propose an improved protocol from the protocol of Harn et al. In our protocol, the size of a broadcasted message from the KGC is fixed, and each group member only needs to compute a fixed-degree interpolating polynomial to recover the group key. Thus, our protocol can be suitable for large-size groups. On the other hand, in the protocol of Harn et al., the KGC should be mutually trusted because it knows all group keys for every communication. If the KGC is untrustworthy, it can bring great threats to the group communications. In this paper, we also propose another improved group key transfer protocol based on untrustworthy KGC. Copyright © 2012 John Wiley & Sons, Ltd.