One-Round Cross-Domain Group Key Exchange Protocol in the Standard Model

摘要

Cross-domain group key exchange protocols enable participants from different domains, even with various cryptographic settings and system parameters, to establish a common secret session key. In prior cross-domain key exchange works, only the case of two communication parties is considered, and the two parties are required to adopt a common cryptographic setting (e.g., identity-based setting) or shared parameters (e.g., algebraic group), which is not suitable for group data sharing in many cross-domain interoperability scenarios. In this paper, we present the first one-round cross-domain group key exchange protocol, and by using indistinguishability obfuscation as the main tool, we prove our construction can achieve the desired security properties in the standard model. It is especially attractive for our protocol that existing PKIs can be used and all participants do not have to accommodate any other peers (even do not need to know other peers' algebraic settings) to agree on the session key.