Financial data such as receipts have to comply with strict archiving
regulations, especially when the archive is to be digital only. Pacio
aims at researching techniques for long-term archival of such data in
a distributed and fault tolerant manner, which additionally lends
itself to rigorous examination by auditors. State of the art
technology for such archives relies on physical and logical
isolation from unlawful modification or otherwise non-compliant
tampering with the data stores. Because of that, these approaches are
expensive, do not scale well, and require faith of both users and
auditors in the correctness of their implementation.
In Pacio, Deepshore and ZIB collaborate to harness the scalability and
robustness of fault tolerant file systems to provide long-term and
robust storage of general data. Credibility and auditability of these
data is established by exploiting the trust created through histories
of proofs of data possession and replication as found in blockchain
technology. Specifically, ZIB will research protocols and algorithms
that merge tamper-proof and scalable storage of data in a distributed
file system with a complete record of the full history of
modifications using a blockchain as metadata store. The major
challenges include guaranteeing availability and integrity of data at
all times by continuously having participants prove the possession of
their assigned data, automatic re-replication if data is found to be
either missing or inconsistent, and prevention of accidental or
deliberate loss of data.
