SDN can stand for: S4C Digital Networks, UK TV company SAP Developer Network Sandane Airport, Anda, Norway Scottish Daily News, a newspaper published in 1975 Scottish Digital Network, proposed
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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1411e2065dfa14f0eb4ad3acd588ed7a339787db307bc98428acd9a0671e2fba. Chain 2 (Bitcoin): anchored in block 954342 (2026-06-19T03:22:39Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/87f3287a-3734-4918-80a5-8fec478eb001.json and https://artists.proofprofile.net/proofs/artist/87f3287a-3734-4918-80a5-8fec478eb001.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).