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 0x76cd16288e9fc8bd3093831841c594dbf8e6b018899d1c3ec1d4cb5c5f9d36dd. Chain 2 (Bitcoin): anchored in block 953770 (2026-06-15T09:50:11Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/a8cb3a77-b749-49f9-94e7-d26e23fec933.json and https://artists.proofprofile.net/proofs/artist/a8cb3a77-b749-49f9-94e7-d26e23fec933.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
1. Confirm isrcCode identifies the recording in the pre-2022 source corpus and cc-db-prod record 2. GET OTSVerificationAPI → server-side canonical-record, hash, and attestation checks must pass 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. Confirm CopyrightID is the CopyrightChains transaction hash 5. If all match: the cc-db-prod record is independently anchored on Bitcoin at OTSTimestamp 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 0xdc53e18c2369dff233b06d8721d1432223723f3cfa17b63dbf1bb8e40071e2c9. Chain 2 (Bitcoin): anchored in block 958942 (2026-07-21T00:24:07Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/TCAFM2198416.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x22cbfc72025a98b8b4186707db4be557e75715a62c43d465b6d83ea585fa5a9d. Chain 2 (Bitcoin): anchored in block 958245 (2026-07-16T05:50:22Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/TCAFT2150126.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x22038b717f6b26655a5d9ffd29239bc9a86feed2b504da095cfb54986292af3d. Chain 2 (Bitcoin): anchored in block 958329 (2026-07-16T21:48:38Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/TCAFW2197006.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x37009e11fd15d1ef91c58f18a534782d4519dd70f9c9d8d528242736bf65b3ab. Chain 2 (Bitcoin): anchored in block 956634 (2026-07-04T10:04:33Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/TCAGF2267594.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3cf1a2dfa83a754a5ec89b93671adc9d15f0fd1536272a026363a80cda714544. Chain 2 (Bitcoin): anchored in block 958992 (2026-07-21T10:12:17Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/TCAGI2218962.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x049cdd2d521a1bc1f777c046af249227b9e21030af31d027abfbe5bf0a944a46. Chain 2 (Bitcoin): anchored in block 958567 (2026-07-18T15:22:40Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/TCAGS2212427.