Identity protocol v1

Design goals

Decentralized identity.

• Has some creation cost
• Sacrifice may be digitally proven, bootstrapping root of trust from blockchain data
• Start as anonymous; opt out of anonymity by attaching identifying key-value pairs (real.name = "John Smith").

Creating sacrifice transactions

Similar to Announce/Commit Sacrifices

1. TM = current block height
2. create transaction T2.
   1. must include OP_RETURN <digest of master pubkey> output
   2. nlocktime = TM + 144 blocks
   3. no more than 1000 bytes in size
3. create transaction T1
   1. must include >= 0.01 BTC fee
   2. must include OP_RETURN txid(T2) output
   3. no more than 1000 bytes in size
4. broadcast T1, T2 until confirmed

Creating root record

Craft a bytestream that represents the root SIN record.

1. MPK = master public key
2. B1 = block w/ T1, B2 = block w/ T2
3. Verify B2 height >= 144 blocks of B1 height. Fail and waste sacrifice if not.
4. MD = ripemd160(MPK)
5. Prefix = 0x18, SIN_Version = 0x01
6. SIN = base58_encode_check( Prefix + SIN_Version + MD )
7. PPK = Preferred Public Key, new public key for root of trust
8. Build root record,
   1. SIN
   2. MPK

Thus a minimal root record is

• SIN
• MPK

and is provably

• linked to the sacrifices
• MPK starts a new chain of digital signature trust, for further record updates

After that, additional key-value pairs may be associated with the root record via updates verified by PPK, stored in an alt-blockchain or DHT somewhere. That is outside the scope of this minimal document.