The Computer Journal Advance Access published online on June 19, 2009
The Computer Journal, doi:10.1093/comjnl/bxp060
Multicast Key Management without Rekeying Processes
1 Department of Management Information Systems, National Chung Hsing University, 250 Kuo-Kuang Rd., Taichung 402, Taiwan, R.O.C
2 Department of Computer Science and Engineering, National Chung Hsing University, 250 Kuo-Kuang Rd., Taichung 402, Taiwan, R.O.C
* Corresponding author: iclin{at}nchu.edu.tw
Received 16 April 2008; revised 24 May 2009
Secure multicast provides efficient delivery which includes an identical data from a source to multiple receivers. A common solution is to apply a symmetric key that is used to encrypt the transmitted data. However, the heavy cost of the rekeying process is the main problem in large and dynamic multicast groups. The tree-based architecture is widely used to reduce the rekeying cost in terms of storage, transmission and computation. However, it usually requires extra overhead to keep key tree balance which is in order to achieve logarithmic rekeying cost. In this paper, we shall propose a new RSA-like multicast key management scheme to solve the rekeying problem. Our protocol applies a star-based architecture to eliminate the rekeying processes and provide the good performance when the membership changes in a multicast group. Furthermore, we also provide an extended multicast scheme, in which we combine public-key and symmetric-key cryptosystems to enhance the performance of multicast encryption.
Key Words: group communication • rekeying, key management, secure multicasting