  The state-of-the-art for auditing and reproducing scientific applications on
high-performance computing (HPC) systems is through a data provenance
subsystem. While recent advances in data provenance lie in reducing the
performance overhead and improving the user's query flexibility, the fidelity
of data provenance is often overlooked: there is no such a way to ensure that
the provenance data itself has not been fabricated or falsified. This paper
advocates to leverage blockchains to deliver immutable and autonomous data
provenance services such that scientific data are trustworthy. The challenges
for adopting blockchains to HPC include designing a new blockchain architecture
compatible with the HPC platforms and, more importantly, a set of new consensus
protocols for scientific applications atop blockchains. To this end, we have
designed the proof-of-scalable-traceability (POST) protocol and implemented it
in a blockchain prototype, namely SciChain, the very first blockchain system
for HPC. We evaluated SciChain by comparing it with multiple state-of-the-art
systems; Experimental results showed that SciChain guaranteed trustworthy data
while incurring orders of magnitude lower overhead.
