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 0x06b8f7978833d312451982a4ca96b4a09de666dec20801e5a3d4a7fdd260c737. Chain 2 (Bitcoin): anchored in block 953772 (2026-06-15T10:33:29Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/c4a5d335-5665-4d70-86b8-19a66e731be6.json and https://artists.proofprofile.net/proofs/artist/c4a5d335-5665-4d70-86b8-19a66e731be6.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 0x05f178b750c507e922304571c9d0f4f5aa00c09cc074237e2f730ef920586b87. Chain 2 (Bitcoin): anchored in block 958063 (2026-07-14T21:07:34Z), 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/TCAHU2423473.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb087d1b18333acaaac2ab34ec30551ac1bc6bed49b7a326d74c53c3e886e5955. Chain 2 (Bitcoin): anchored in block 956545 (2026-07-03T19:59:51Z), 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/TCAIB2428025.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xad64bb9876d774e48fb9ddf8a23c869f7759d2906b1dc7a7ddd85daafa83a1a2. Chain 2 (Bitcoin): anchored in block 958476 (2026-07-18T01:26:56Z), 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/TCAIH2489755.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xeb5b0a3d8a806fa6d7a74217a10e3d16a1d46ea2d843f1a4d900e029a5a1dde4. Chain 2 (Bitcoin): anchored in block 956822 (2026-07-05T18:48:28Z), 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/TCAIK2464439.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x96f8e802ece05eb19e23fe4b4d4cc054e62652d1cf2ca0c6b8ef8777e815b50b. Chain 2 (Bitcoin): anchored in block 956474 (2026-07-03T08:56:35Z), 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/TCAJB2444835.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe8b3e57e3148d843fdc557e1ca730baddb9bc9cf8ca80ce3ee8feb96525b1368. Chain 2 (Bitcoin): anchored in block 958331 (2026-07-16T21:55:37Z), 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/TCAJR2560330.