| Internet-Draft | VTL | August 2026 |
| El Khatabi | Expires 14 February 2027 | [Page] |
This document profiles a verifiable-telemetry ledger. Its interoperability boundary begins with exact canonical-record byte strings that an upstream system has already produced. The profile fixes admission and assignment of those byte strings to serial-numbered segments, deterministic commitment-tree calculation, an authoritative segment artifact encoded in Concise Binary Object Representation (CBOR), a producer manifest, three disclosure classes, and binding of the authoritative segment artifact digest to external timestamp channels. Transport framing, decryption, anti-replay processing, payload interpretation, and source-telemetry-to-record mapping are outside this profile. Segment closure uses a deployment-configured elapsed-time interval and does not depend on calendar dates from either the source or the ledger producer. Every baseline producer selects the RFC 3161 timestamp channel, as updated by RFC 5816 and profiled by this document, for every emitted segment. OpenTimestamps (OTS) can be selected only as an additive, deployment-specific timestamp profile; peer signatures are optional attestations.¶
The profile enables independent recomputation and audit of disclosed evidence from the admitted canonical-record bytes onward. It does not verify how source telemetry was authenticated, interpreted, or mapped to those bytes, and it does not cover device onboarding, end-to-end security of sensor values, or safety decisions.¶
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