F2F may refer to: Friend-to-friend, a type of private P2P computer network Firewall-to-firewall transfers, an important part of most modern P2P network designs FAI CLASS F2F - Diesel Powered Pro
1. Compute SHA-256 of OTSCanonicalRecord value → must equal OTSHash 2. Open OTSProofURL → extract Bitcoin block number → must equal OTSBitcoinBlock 3. GET OTSBitcoinBlockVerifyURL → returns the Bitcoin block hash at height OTSBitcoinBlock; GET https://blockstream.info/api/block/{that hash} → its timestamp must match OTSTimestamp 4. Read CopyrightID inside OTSCanonicalRecord → must equal the CopyrightID above 5. GET OTSVerificationAPI → pre-computed 6-check result from server 6. If all match: this entity was registered on CopyrightChains at OTSTimestamp, independently verifiable on Bitcoin Note: an OTS proof may carry multiple Bitcoin attestations; OTSBitcoinBlock is the earliest confirmed one — a later attestation inside the proof corroborates it and is not a mismatch
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc2c506f978c67af83bfea028f9bc90af623ee5b02337365bcae8cc604dd8c95a. Chain 2 (Bitcoin): anchored in block 953875 (2026-06-16T02:12:46Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/07cf2035-107f-4831-808e-658810ef6a06.json and https://artists.proofprofile.net/proofs/artist/07cf2035-107f-4831-808e-658810ef6a06.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).