Proof of preservation & PDP
How continuous, on-chain Proof of Data Possession underpins every guarantee.
Proof of preservation is the heart of Velic. Instead of trusting that your master is safe, you get continuous, on-chain proof that it is, produced by the network, not by Velic.
Proof of Data Possession (PDP)
On a fixed cadence, the storage providers holding your master must answer a cryptographic challenge that they can only satisfy if they still hold the data. Each answer is submitted to the PDPVerifier contract on the Filecoin chain and recorded there. The proof is taken against the piece's content address, so a passing proof means the bytes are present and bit-intact.
This happens per dataset, continuously, for the life of the master. It is not a one-time check at upload.
Cadence
- On the Filecoin Calibration network (which this version runs and verifies on), providers prove roughly every 30 minutes.
- On Filecoin mainnet, the cadence is daily.
If proofs stop landing for long enough, a master is flagged degraded rather than silently trusted, so a problem surfaces immediately instead of years later on restore.
What you see
The proof-of-preservation dashboard turns this on-chain record into something readable: when the master was first stored, how many independent copies exist, when it was last verified, and a heatmap of the recent proof history. Each proof record carries an epoch (the Filecoin block height it was proven at) and a proof hash.
Velic never invents a proof
Velic only reports proofs that exist on-chain. A master with no proofs yet is shown honestly as pending: the dashboard reads live verifier state and the recorded proof history, and shows exactly what the chain says.