Abstract: The invention provides a computer-implemented method (and corresponding system) for generating a blockchain transaction (Tx). This may be a transaction for the Bitcoin blockchain or another blockchain protocol. The method comprises the step of using a software resource to receive, generate or otherwise derive at least one data item; and then insert, at least once, at least one portion of code into a script associated the transaction. Upon execution of the script, the portion of code provides the functionality of a control flow mechanism, the behaviour of the control flow mechanism being controlled or influenced by the at least one data item. In one embodiment, the code is copied/inserted into the script more than once. The control flow mechanism can be a loop, such as a while or for loop, or a selection control mechanism such as a switch statement. Thus, the invention allows the generation of a more complex blockchain script and controls how the script will execute when implemented on the blockchain.

Abstract: The invention provides a secure method for exchanging entities via a blockchain. The invention incorporates tokenisation techniques, and also techniques for embedding metadata in a redeem script of a blockchain transaction. Embodiment(s) provide a method of: generating a first script, the first script comprising: a first set of metadata associated with a first invitation for the exchange of a first entity by a first user, the first set of metadata comprising an indication of the first entity to be offered for exchange and a first location condition for the exchange, a first user public key (P1A) associated with the first user, wherein the first user public key (P1A) is part of an asymmetric cryptographic pair comprising the first user public key (P1A) and a first user private key (V1A).

Abstract: A computer-implemented method (600) and system (1) for verifying ownership of a computer software after installation and prior to execution using a distributed hash table (13) and a peer-to-peer distributed ledger (14). This may be the Bitcoin blockchain or an alternative implementation. The method includes determining (610) a second user public key associated with a second user (24) from a transaction record stored on the peer-to-peer distributed ledger (14). A second public key associated with the second user may be determined (620) from an entry on the distributed hash table (13). The method further includes comparing (630) the second user public key and the second public key, and verifying (640) the ownership of the computer software based on the comparing of the second user public key and the second public key.

Abstract: The invention provides a computer-implemented control method and corresponding system. The method may control or influence a device, system or other resource such as a technical process. The invention can provide a mechanism for emulating or otherwise executing the functionality of a logic gate via a computer-based distributed ledger (blockchain). This may be the Bitcoin blockchain or an alternative network/protocol. The invention provides logic embedded within a redeem script such that it determines which particular private keys have been used to sign an unlocking script, and then interprets the provision of those keys in accordance with a predetermined function.

Abstract: A method and system of recording multiple transactions between a multiple of users on a blockchain (9), including a first transaction (22) from a first user (5) to a second user (7) and a second transaction (24) from the second user (7) to the first user (5). The blockchain may be, for example, the Bitcoin blockchain. The method may include receiving (110) a first request from a first node (15) associated with the first user (A) to transfer a first quantity of cryptocurrency associated with the first transaction (22) and receiving (120) a second request from a second node (17) to transfer a second quantity associated with the second transaction (24). The first transaction (22) is conditional on receiving (120) the second request and the second transaction (24) is conditional on receiving (110) the first request. The method also includes verifying (130) the first request and second request that includes determining both the conditional steps of receiving the first request and second request are satisfied.

Abstract: A computer-implemented method (600) and system (1) for verifying ownership of a computer software for installation using a distributed hash table (13) and a peer-to-peer distributed ledger (14). This may be the Bitcoin blockchain or an alternative blockchain implementation. The method includes determining (610) a second user public key associated with a second user (24) from a transaction record stored on the peer-to-peer distributed ledger (14). A second public key associated with the second user may be determined (620) from an entry on the distributed hash table (13). The method further includes comparing (630) the second user public key and the second public key, and verifying (640) the ownership of the computer software based on the comparing of the second user public key and the second public key.

Abstract: This invention relates generally to blockchain implementations and is suited for, but not limited to, use with the Bitcoin blockchain. It can be used for the implementation of automated processes such as device/system control, process control, distributed computing and storage and others. The invention provides a solution which uses a blockchain to control a process executing on a computing resource. In a preferred embodiment, the computing resource, running simultaneously and in parallel to the blockchain, manages a loop-based operation. The computing resource continuously monitors the state of the blockchain as well as any other off-blockchain input data or source. The execution of the loop is influenced by the state of the blockchain. Each iteration of the loop that is executed by the computing resource is recorded in a transaction that is written to the blockchain. It is stored as a hash within the transaction's metadata.

Abstract: In accordance with the invention there may be provided a method and corresponding system for controlling the performance of a process conducted via a blockchain. The blockchain may or may not be the Bitcoin blockchain. The process may be a lending process. Advantageously, the invention provides a mechanism which enables the ultimate owner of a property or other asset to borrow funds against that asset, and sets out how this can be achieved in a manner which does not require the return to the investor(s) to be determined through the payment of interest. This makes it compliant with non-interest forms of lending. The invention provides a blockchain-implemented method (and corresponding system) of embedding data in a blockchain transaction (Tx). The method comprises the steps of deriving a public-key-private key cryptographic pair for the data; deriving a signature for the data using the public key-private key cryptographic pair; codifying the data to generate codified metadata for the data.

Abstract: There may be provided a computer-implemented method. It may be implemented at least in part using a blockchain network such as, for example, the Bitcoin network.

Abstract: The invention relates to blockchain technologies such as the Bitcoin blockchain, and the tokenisation of assets or entities. It is particularly suited for implementing a payroll on a blockchain platform and comprises a method (100) and system (1) of transferring cryptocurrency from a first node (3) to a second node (7). Both nodes (3, 7) are associated with a payroll and have a respective asymmetric cryptography pair, each pair including a master private key and a master public key. Respective additional private and public keys may be determined based on the master private key, master public key and a generator value at each node. The additional private and public keys may form a hierarchical structure. A common secret may be determined at each of the nodes (3, 7) based on the additional private and public keys. The common secret may be used to securely transmit confidential information across a communications network (5).

Abstract: The invention relates to the fields of tokenisation, blockchain and smart contract technologies. It provides a technical arrangement which simplifies the automated management of contracts. The invention comprises a method and system which use a computer-based repository for storage of the contract. The contract is then represented by a transaction on the blockchain. Metadata within the transaction's script includes a hash of the contract and a means of identifying its location within the repository. The transaction also includes an unspent output (UTXO) which indicates its status as an open (ie not terminated) contract. The contract is terminated by spending the output at a later point in time, for example, using n Lock Time+Check Lock Time Verify (CLTV). By combining this concept with other techniques and computing components, the invention can provide a powerful mechanism for implementing various tasks such as renewing or rolling over the contract, or dividing it into sub-contracts or conditions.

Abstract: A method of communicating a secret (k0, k1) on the Bitcoin blockchain is disclosed. The method comprises sending information identifying secrets selectable by the recipient and receiving a first public key (Ui) of an elliptic curve cryptography system, corresponding to a first secret (Si) selected for access by the recipient and for which a first private key (m) is accessible to the recipient. A second public key (U1-i) is received, corresponding to a second secret not selected for access by the recipient, wherein a corresponding second private key is not available to the recipient. First and second secrets encrypted by means of the respective first and second public keys (X0, X1) are sent to the recipient, wherein the first secret is accessible to the recipient by means of the first private key, the second secret is inaccessible to the recipient, and the sender is unable to distinguish between the first and second secrets.

Abstract: A computer-implemented access method is provided. The method comprises the steps of: (i) submitting, to a blockchain (such as the Bitcoin blockchain), an access blockchain transaction addressed to a derived public key derived at least in part from a secret value and a public key; (ii) generating a verification public key based at least in part on the secret value and the public key; (iii) comparing the derived public key and the verification public key; and (iv) based on the comparison of step (iii): (a) allocating the at least one of the derived and verification public key as a further public key for verifying a further derived public key; and (b) granting access to a resource associated with at least one of the secret value and the derived public key.

Abstract: A computer implemented voting process (2) for executing a blockchain transaction, such as a transaction on the Bitcoin blockchain, is disclosed. The process comprises distributing shares (6) of a first common secret among a plurality of participants (4), wherein the first common secret implements an automated voting process (14) by the participants and is accessible to a first threshold number of shares and is inaccessible to less than the first threshold number of shares. The process further comprises determining (10, 12), based on different numbers of said shares of the first common secret held by a plurality of the participants, at least one combination of shares held by a plurality of the participants, to provide the first threshold number of shares.

Abstract: A plurality of nodes implemented by computing devices in a network include sender and recipient nodes. The sender node sends, to the validation node, a request to transfer an amount of virtual currency from a sender account (associated with transaction receipts) to a recipient account. The request includes first copies of the receipts or references thereto. The validation node requests second copies of the receipts from at least two of the nodes, and receives the second copies from fewer than all of the nodes. The validation node determines whether the first copies have been tampered with by comparing the first and second copies to one another. When tampering has not occurred, at least one new receipt is generated indicating the amount has been transferred. Then, the at least one new receipt is forwarded to fewer than all of the nodes for storage.

Abstract: The invention provides mechanisms for enhancing the security and protection of a computer-based system or network. It relates, in part, to the use of a decoy (which may be termed “honeypot” or “honeynet”) for collecting attacker-related data, and/or diverting malicious behaviour away from legitimate resources. In one embodiment, the invention provides a method comprising the steps of receiving, processing and logging network traffic data of a plurality of users, where the network traffic is received from a plurality of participating users; determining an attacker profile from the network traffic data; determining a honeypot or honeynet configuration based on the attacker profile; and upon receipt of a valid information request from a user of the plurality of users, providing the determined attacker profile and configuration to the user.

Abstract: A method (400) of encrypting data at an electronic device (3) where the electronic device is associated with a key device (5). Each device is associated with an asymmetric cryptography pair, each pair including a first private key and a first public key. Respective second private and public keys may be determined based on the first private key, first public key and a deterministic key. A secret may be determined based on the second private and public keys. The data at the electronic device (3) may be encrypted using the determined secret or an encryption key that is based on the secret. Information indicative of the deterministic key may be sent to the key device (5) where the information may be stored.

Abstract: A solution for controlling access to a resource such as a digital wallet implemented using a blockchain. Use of the invention during set up of the wallet can enable subsequent operations to be handled in a secure manner over an insecure channel. An example method comprises splitting a verification element into multiple shares; determining a common secret at multiple nodes in a network; and using the common secret to transmit a share of the verification element between nodes. The shares can be split such that no share is sufficient to determine the verification element and can be stored at separate locations. Upon share unavailability, the share can be retrieved a location accessibility. For safe transmission of the share(s), the common secret is generated at two different nodes independently and used to generate an encryption key for encrypting at least one share of the verification element to be transmitted securely.

Abstract: A method (300) and system (1) of determining a common secret for two nodes (3, 7). Each node (3, 7) has a respective asymmetric cryptography pair, each pair including a master private key and a master public key. Respective second private and public keys may be determined based on the master private key, master public key and a deterministic key. A common secret may be determined at each of the nodes based on the second private and public keys. In one example, a node (3, 7) may determine the common secret based on (i) a second private key based on the node's own master private key and the deterministic key; and (ii) a second public key based on the other node's master public key and the deterministic key. The invention may be suited for use with, but not limited to, digital wallets, blockchain (e.g. Bitcoin) technologies and personal device security.

Abstract: A computer-implemented method (900) and system (1) for verifying the integrity of a computer software for installation using a distributed hash table (13) and a peer-to-peer distributed ledger (14). This may be the Bitcoin blockchain or an alternative implementation. The method includes determining (910) a metadata associated with a transaction record stored on the peer-to-peer distributed ledger (14). An indication of an entry stored on the distributed hash table (13) may be determined (920) from the metadata. The method further includes determining (930) a third hash value based on the computer software and determining (940) a fourth hash value from the entry on the distributed hash table (13). The method further includes comparing (950) the third hash value and the fourth hash value and verifying (960) the integrity of the computer software based on the comparing of the third hash value and the fourth hash value.