Authenticated Range Querying of Historical Blockchain Healthcare Data using Authenticated Multi-Version Index

With growing adoption of blockchain in established and emerging applications, there is an increasing need to support efficient ad hoc querying of authenticated historical data. This is especially true in fields such as healthcare to meet the rigorous security and regulatory requirements of ever-expanding digital health platforms. Existing blockchain systems, however, offer little or no support for querying capabilities over historical data. Although a full blockchain archive node can be used to maintain historical records of all executed transactions on the chain, it is not scalable when dealing with large volumes of data. Moreover, such ‘offline’ historical data lack tamper evidence support. To address these issues, we introduce an authenticated index structure called Authenticated Multi-Version Skip List (AMVSL), designed to support a rich set of query features over historical blockchain data. We further present three range queries: SVRK, MVRK and MVAK, which offer querying over a range of keys and a range of versions. Our experimental evaluation of two healthcare-inspired examples demonstrates that AMVSL efficiently supports these queries and can achieve performance that is several orders of magnitude faster than existing authenticated data structures.