GDPR compliance says who may process data; it does not prove that stored records are still the records that were written. In a tele-assistance setting that gap matters: if a monitoring stream is altered, the provider may act on false information about a vulnerable person, and nothing in a conventional database makes the alteration visible.
The M-Sec Blockchain Middleware addresses integrity rather than confidentiality. Data itself can remain off-chain in an encrypted database; what goes on-chain is a hash — an alphanumeric fingerprint derived from the data. Because any change to the underlying record produces a different hash, tampering becomes detectable by comparison. Entries registered on the distributed ledger cannot be erased or rewritten, so the audit trail is both quick to check and hard to dispute.
The component was developed in the M-Sec project by researchers at ICCS – National Technical University of Athens, alongside partners at Keio University and CEA.
– Hash anchoring of off-chain records on a distributed ledger
– Tamper detection by hash comparison
– Immutable, append-only audit trail
– Works with existing encrypted databases rather than replacing them
– Integration with the wider M-Sec security stack: access control, marketplace, data-subject rights
Deployed in the Santander home monitoring pilot (M-Sec Use Case 2) to protect the integrity of sensor records from participants’ homes. The pilot also produced a hard lesson about deployment topology: the middleware was hosted in Greece, and downtime caused by the major Greek wildfires of 2021 had to be worked around by writing a bridge that let the rest of the system keep running without it.
Get in touch to explore deployment opportunities or propose a complementary approach.
