A Compromise-Tolerant Key Management Framework for Private Blockchain

摘要

One major threat for enterprise private blockchains is the compromise of the trust-enabling Public Key Infrastructure (PKI). While the invention of private blockchains has addressed the trust problem in inter-organisational information sharing, the confidentiality, integrity, and availability of information within one organisation is still reliant on traditional, centralised key management like PKI. This design has introduced a number of risks including: a) trust reliance on a few people creating an insider threat vulnerability; b) potential loss of assets, reputation, and privacy; c) single-point-of-failure; and d) defeating the distributed trust introduced by the invention of public blockchains. To mitigate these risks, this work proposes a compromise-tolerant key management approach that combines decentralised blockchain-based trusted PKI with the enforcement of multi-signature and smart contract features. Using a multi-signature feature allows the combination of decentralised blockchains and centralised PKIs, whereas smart contract enables key management transparency among all network participants to establish the distributed trust and mitigate insider and outsider threats.