Issue No. 09 - September (2005 vol. 17)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/TKDE.2005.152
Recently, Chien proposed a time-bound hierarchical key assignment scheme based on tamper-resistant devices. Without public key cryptography, Chien's scheme greatly reduces computation load and implementation cost. In this paper, we show that Chien's scheme is insecure against a collusion attack whereby three users conspire to access some secret class keys that they should not know according to Chien's scheme.
Index Terms- Cryptography, hierarchical key assignment.
Xun Yi, "Security of Chien's Efficient Time-Bound Hierarchical Key Assignment Scheme", IEEE Transactions on Knowledge & Data Engineering, vol. 17, no. , pp. 1298-1299, September 2005, doi:10.1109/TKDE.2005.152