Verflog

Verflog is a log format and data structure designed to record sequences of events in distributed and regulated environments with an emphasis on verifiability and tamper resistance. An entry typically contains a timestamp, an event identifier, a cryptographic hash of the payload, and a pointer to the previous entry, forming an append-only chain. To enable external verification, entries are organized into blocks or segments that produce a verifiable root hash through a Merkle tree or similar authenticated structure. The root can be signed by a trusted authority, allowing auditors to confirm that a given set of records existed at a specific time without exposing every detail.

Origin and use: The term emerged in discussions around auditable logs and regulatory compliance in the 2020s and refers to a family of designs rather than a single standard. Verflog designs prioritize data integrity, availability, and privacy controls, offering mechanisms for selective disclosure by revealing payload hashes or redacted data along with cryptographic commitments.

Applications: Verflog includes incident investigation trails, regulatory audit logs, supply chain provenance, and interoperability layers in blockchain-inspired systems where a reliable history is required. Implementations vary in payload formats, cryptographic schemes, and access controls, but common themes are append-only guarantees, cryptographic chaining, and publicly verifiable proofs of inclusion or timestamping. Related concepts include append-only logs, audit trails, and Merkle-tree based proofs.