DLPKH - Distributed Logical Public-Key Hierarchy

Decentralized group key management schemes for supporting secure group communication systems have been studied in the two flavors of contributory key agreement and decentralized key distribution. However, the primary focus has been on the former because the latter have been criticized for additional overheads of establishing secure channels and for the possibility of weak keys produced by the generating entity. In this work we develop a novel decentralized key distribution that uses public-key trees to eliminate the overheads of establishing secure channels and employs a practical approach of partial contribution to minimize the possibility of weak keys. The result is a simple and secure scheme whose performance is significantly better than previous schemes that involve contribution or distribution.