Secure Collaboration Between Consortiums in Permissioned Blockchains.

Secure collaboration between consortiums is imperative for the distributed applications deployed on distinct permissioned blockchains or consortium blockchains to provide superior services. The collaboration can be realized by cross-chain transactions processed by cross-chain protocol. The previous two-phase commit and two-phase locking cross-chain protocol are unable to be applied in the scenario where the consortium can be malicious. In this work, we propose the ledger framework of the multiple consortium blockchain systems including the global cross-chain ledger. The cross-chain ledger establishes the order relationship between cross-chain sub-transactions defined in the cross-chain protocol and adopts the hierarchical Byzantine fault-tolerant consensus to tolerate malicious consortiums. We also give two instances of the framework. Based on the cross-chain ledger, we propose the revoke operation in the two-phase commit and two-phase locking cross-chain protocol. We also make the protocol secure in the presence of malicious consortiums and prove its security. Finally, we conduct comprehensive experiments to characterize the performance of the two instances and the cross-chain protocol. The experimental results reveal the efficiency of our scheme even in the presence of malicious consortiums.