Computer-implemented system and method for determining the state of a machine executable contract implemented using a blockchain

Patent metadata

Field	Value
Publication number	US-2020005285-A1
Application number	US-201816482227-A
Country	US
Kind code	A1
Filing date	Jan 29, 2018
Priority date	Jan 31, 2017
Publication date	Jan 2, 2020
Grant date	—

Abstract

Computer-implemented systems and methods are detailed for establishing information on states of a machine executable contract, for instance in the context of unspent transactions (UTXOs), blockchain and deterministic finite automaton (DFA) implementation of contracts and the determination of states within those. The stages can include determining the information of interest and the codes or tags identifying that information, constructing the metadata associated with those codes or tags, combining that with a public key for an agent that will be associated with the information. The scriptPubKey values of each script may be used to provide the keys for use in constructing an external database and more specifically mapping the keys from the scriptPubKey values, linked to the information of interest. To obtain the other half of the combination, there is a derivation of the script hash addresses from the scriptPubKey values, with those being used to populate a digital wallet. A search and match algorithm is then used to find UTXO's with matching script hash addresses on the blockchain. These then populate the aforementioned database with UTXO's that match to the script hash addresses and hence to the keys to complete the combinations. A match indicates in a definitive manner the state.

First claim

1 . A method of determining a state of a machine-executable contract implemented on a blockchain, the method including:
a) determining information of interest and generating a cryptographic key related to that information of interest; b) constructing a search term related to the cryptographic key; c) searching the blockchain for unspent outputs (UXTO's) matching the search term, wherein the information of interest is a state of a machine-executable smart contract, and the method further comprises: d) extracting information from the unspent outputs (UXTO's) matching the search term, and e) determining the state of the machine-executable smart contract from the extracted information.

2 . A method according to claim 1 , wherein the machine-executable smart contract is implemented using a deterministic finite automaton and the step of determining the state of the machine-executable smart contract comprises determining a state of the deterministic finite automaton.

3 . A method according to claim 1 , in which the cryptographic key is generated by applying a reproducible process to the information of interest, the same reproducible process having generated the information contained in unspent outputs (UXTO's) of the blockchain being searched for.

4 . A method according to claim 1 , in which the search term is constructed from the cryptographic key.

5 . A method according to claim 1 , in which the searching is provided by a search and matching stage and unspent outputs (UXTO's) matching the search term are paired with the cryptographic key and/or with the information of interest.

6 . A method according to claim 5 , in which the pairing(s) are provided within a database.

7 . A method according to claim 1 , in which the method includes a specification stage, the specification stage including selecting the information of interest and including a code or tag specification stage.

8 . A method according to claim 1 , in which the method includes a metadata construction stage, the information of interest and/or a code or tag therefor being converted to metadata.

9 . A method according to claim 8 , in which the metadata is incorporated into a public key, designated an information public key.

10 . A method according to claim 1 , in which an agent association stage is provided to select one or more agents, one or more or all of the selected agents providing public keys designated agent public keys.

11 . A method according to claim 9 , in which the method provides a combination stage, the combination stage combining the information public key with one or more agent public keys and generating a locking script.

12 . A method according to claim 11 , in which the combination stage generates a hash of the locking script.

13 . A method according claim 1 , in which the method includes a valuing stage to obtain a value, from a locking script or a hash of a locking script, to provide the cryptographic key.

14 . A method according to claim 1 , in which the method includes a databasing stage and the databasing stage includes mapping information of interest to a cryptographic key and the mapping of information to the cryptographic key provides one half of a mapping of a combination to the cryptographic key.

15 . A method according to claim 1 , in which the method includes an address derivation stage to derive address(es), the address(es) being derived from a locking script or from a hash of a locking script.

16 . A method according to claim 1 , in which the method include a search and matching stages, the search and matching stage including looking in the blockchain for one or more matches with an address or addresses, the search and matching stage acquiring details of UTXO's in the blockchain which match to the address or addresses used in the search.

17 . A method according to claim 14 , in which a search and matching stage and/or a databasing stage, maps acquired details of UXTO's matching an address to the cryptographic key, the mapping providing the other half of the combination related to the cryptographic key.

18 . A computer implemented system, arranged to implement the method of any of claim 1 .

19 . The computer implemented system of claim 18 , further comprising:
at least one computing agent arranged to implement a DFA via a blockchain; and a blockchain platform.

Assignees

• Nchain Holdings Ltd

Inventors

• Jimenez-Delgado Pedro

Classifications

• G06Q20/405

  Establishing or using transaction specific rules · CPC title

• G06Q10/103 Primary

  Workflow collaboration or project management · CPC title

• H04L9/3239

  involving non-keyed hash functions, e.g. modification detection codes [MDCs], MD5, SHA or RIPEMD · CPC title

• H04L9/0637

  Modes of operation, e.g. cipher block chaining [CBC], electronic codebook [ECB] or Galois/counter mode [GCM] · CPC title

• G06Q20/0658

  e-cash managed locally · CPC title