Content Provenance Profile (CPP) Core

The Content Provenance Profile (CPP) is an open specification for cryptographically verifiable media capture provenance. This document defines the core data model, hashing conventions, Merkle tree construction rules, RFC 3161 Time-Stamp Authority (TSA) anchoring protocol, and offline verification procedures for CPP. CPP enables capture devices to produce tamper-evident provenance records that bind media content to external timestamps via trusted third parties. Unlike self-attestation models, CPP requires independent timestamp verification through RFC 3161 TSA services, providing externally verifiable proof of when media was captured. This revision (-01) incorporates implementation experience from multi-platform deployments, adding self-attested signer identity, hardware-backed key requirements, chain context for partial submission detection, depth analysis extensions for screen detection, and a Pre-Publish Verification Extension for social media sharing workflows. It also defines interoperability mappings with the C2PA specification.