Abstract: An implementation of the present application provides a computer—implemented method to increase the security of a blockchain—implemented transaction, the transaction including participation from a plurality of participating nodes, each participating node participating as a message originator, selector, and propagator. The method, implemented at a participating node, includes: receiving ciphertext from a prior node and determining whether the participating node is a selector node for said ciphertext received from the prior node. When the participating node is the selector node for said ciphertext, the method includes selecting a subset of said ciphertext, decrypting the selected subset of said ciphertext to provide opted ciphertext and transmitting said opted ciphertext to the next node. When the participating node is other than the selector node for said ciphertext, the method includes decrypting said ciphertext received from the prior node and transmitting the decrypted ciphertext to the next node.

Abstract: A computer-implemented method of distributing a shared secret, such as a transaction on the Bitcoin blockchain among a plurality of participants is disclosed. The method comprise a mapping step wherein a plurality of inputs to the mapping step are mapped to respective elliptic curve points of an elliptic curve of an elliptic curve cryptography system common to the participants. In a first encryption step, a plurality of said elliptic curve points are encrypted by means of a public key of a public-private key pair of the elliptic curve cryptography system to provide an output adapted to be decrypted by means of the corresponding private key of the public-private key pair, and in a second encryption step wherein a plurality of parts of at least one input to said second encryption step are multiplied by respective terms of a series known to said participants.

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: A method of storing data on a blockchain, such as the bitcoin blockchain, is disclosed. The method comprises generating a blockchain transaction having at least one first input and/or at least one first output containing first data (<Content 1>) to be stored on the blockchain, and at least one second input and/or at least one second output containing second data (<Attribute 1>,<Attribute 2>) representing at least one attribute of the first data. At least one second input and/or at least one second output is separate from the or each first input and/or first output.

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: A method of obtaining digitally signed data is disclosed. The method comprises sending first data (e2) from at least one of a plurality of first participants to at least one second participant, wherein the first data is based on second data (e) accessible to at least one said first participant, and the second data is inaccessible to the or each said second participant. A digital signature (s1) of the first data is received from at least one said second participant, and the digital signature of the first data is processed, by a plurality of the first participants, to provide shares of a digital signature (s) of the second data, wherein the digital signature of said second data is accessible by means of a threshold number of said shares and is inaccessible to less than said threshold number of shares.

Abstract: A computer-implemented method (100) and system (1) for determining a metadata M for securing a controlled digital resource such as computer software using a distributed hash table (13) and a peer-to-peer distributed ledger (14). This is a blockchain such as the Bitcoin blockchain. The method includes determining (110) a data associated with the computer software and determining (120) a first hash value based on the computer software. A second hash value based on the data and the computer software may be determined (130). The method further includes sending 140, over a communications network (5), the data, the first hash value and the second hash value to an entry for storage in a distributed hash table (13). The second hash value may be a key of a key-value pair. The data and the first hash value may be a value in the key-value pair. A metadata (M) that is based on the second hash value may be determined (150) for storage on the peer-to-peer distributed ledger (14).

Abstract: A method of sharing a first common secret among a plurality of nodes (A, B, C) for enabling secure communication for blockchain transactions such as on the Bitcoin blockchain is disclosed. The method comprises determining, for at least one first node (A) a plurality of second common secrets (SAPC, SAPB), wherein each second common secret is common to the first node and a respective second node (B), is determined at the first node on the basis of a first private key of the first node (SA) and a first public key of the second node (PC, PB) and is determined at the second node on the basis of the first private key of the second node (SB, SC) and the first public key of the first node (PA). A third common secret (SBPC, SCPB) common to the second node (B) and a third node (C) is determined for the second node. The method comprises encrypting, at the first node, shares of the first common secret known to the first node, and sending the encrypted shares to the second nodes.

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: A computer-implemented method is disclosed. The method includes providing a blockchain transaction comprising a public key combination verification function. The blockchain transaction is configured to be redeemable to permit access to, or transfer control of, a resource by providing to the blockchain transaction an input comprising: a plurality of public keys; a gradient value (k) related to two of the plurality of public keys; and a group public key derived from a combination of the public keys and the gradient value (?). The blockchain transaction is configured to apply the public key verification function to the input to verify, upon successful redemption of the transaction, that the group public key is derived from the combination of the plurality of public keys.

Abstract: The invention provides a generic operating system for coordinating, controlling and/or influencing the activities of a device. The invention is implemented using a blockchain platform with which the operating system is arranged to interact. The blockchain may be the Bitcoin blockchain. In a preferred embodiment, the device is an Internet of Things (IOT) device. The invention provides a computer-implemented control system and corresponding method for controlling a device, the system comprising a device configured for wireless communication with a network and having an IP address and a public-private key cryptographic key pair associated with the device; a software-implemented control component arranged to monitor the state of a blockchain network and/or transmit blockchain Transactions to the blockchain network; and a set of instructions arranged for execution by the control component to control the functionality of the device.

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: 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 exchange method is provided. The method may be performed on one or more blockchains, such as the Bitcoin Cash blockchain. The method comprises the steps of: communicating a first veiled secret value (H(A0)) from a first user to a second user and a second veiled secret value (H(B0) from the second user to the first user; and constructing first and second blockchain transactions (tx1, tx2) each comprising the first veiled secret value and the second veiled secret value, the transactions arranged to be unlockable to transfer control of a respective first or second resource upon provision of both the first secret value (A0) and the second secret value (B0) to the respective blockchain transaction, wherein unlocking of the first blockchain transaction causes a first secret value to be revealed to the second user, and unlocking of the second blockchain transaction causes a second secret value to be revealed to the first user.

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 an event detecting, monitoring and/or counting mechanism. The event may be, for example, a vote, decision or selection which is made by a given entity. The invention provides a counting solution in which a 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: A computer-implemented security method is provided. The method may be implemented on one or more blockchains, such as the Bitcoin Cash blockchain.

Abstract: A computer-implemented access method is provided. The method comprises the steps of: (i) providing a verification data item of a one-way function chain of data items; (ii) submitting, to a blockchain (such as the Bitcoin blockchain), an access blockchain transaction comprising a data item of the chain; (iii) applying the one-way function to the data item to provide an output; (iv) comparing the output of step (iii) to the verification item to provide an outcome; and (v) based on the outcome of step (iv): (a) allocating the output as a further verification data item for verifying a further data item of the chain; and (b) granting access to a resource associated with the data item.

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.