Abstract: A computer-implemented method for distributing shares of a digitally signed message among a plurality of participants. The method comprising: inputting a digital message to an elliptic curve digital signature algorithm to provide a digital signature; mapping the digital signature to elliptic curve points of an elliptic curve cryptography system common to the participants. In a first encryption step, a knapsack algorithm is applied to the elliptic curve points to generate an encrypted version of the digital signature. In a second encryption step, an elliptic curve cryptography encryption is applied to the encrypted version of the digital signature to provide a doubly encrypted version of the digital signature; and applying a secret sharing step to the doubly encrypted version of the digital signature, wherein the digital signature is fragmented into a plurality of blocks before applying the knapsack algorithm.

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.

Abstract: A method of providing credentials to enable a second party to verify an identity of a first party. The first party is associated with a first public key which is registered with a third party. One or more first credentials are provided to the second party. A request transaction is obtained, which comprises a) an input comprising a signature generated based on a respective private key of the third party, and b) an output locked to a second public key of the first party. The second public key is based on the first public key. A confirmation transaction is generated. The confirmation transaction comprises an input that references the output of the request transaction, and a signature generated based on a private key corresponding to the second public key of the first party. The confirmation transaction is transmitted to nodes of a blockchain network for inclusion in a blockchain.

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: An example electronic computing device can include: a processor; and a system memory, the system memory including instructions which, when executed by the processor, cause the electronic computing device to: receive data associated with risk from various sub-systems of an organization; correlate the data to develop a risk profile for the organization; and present the risk profile in a single user interface.

Abstract: The invention provides improved Simplified Payment Verification (SPV) solutions for blockchain-implemented transfers. It is suited for, but not limited to, implementation in one or more SPV wallets, or on smart cards etc. In accordance with one embodiment, a method, system or resource(s) is provided which enables Alice to transfer an asset to Bob. Bob sends Alice a payment transaction template (template Tx3) and requests: the full transaction data for all input transactions (Tx1, Tx2) comprising at least one output that Alice wants to spend as inputs to a transfer (Tx3); the Merkle path for all input transactions (Tx1, Tx2) linking them to their respective Merkle roots associated with their respective block headers; the completed transfer transaction (Tx3). Alice provides this information plus her signature and optionally a change address.

Abstract: Techniques are provided for a computer-implemented security method implemented on one or more blockchains. The method comprises the steps of: applying a one-way function to a first secret value accessible to a first user to create a first veiled secret value; communicating the first veiled secret value from the first user to a second user; receiving a second veiled secret value from the second user, wherein the second veiled secret value is created by applying a one-way function to a second secret value accessible to the second user; and constructing a first blockchain transaction comprising the first veiled secret value and the second veiled secret value, the first blockchain transaction arranged to be unlockable to transfer control of a first resource upon provision of both the first secret value and the second secret value to the first transaction.

Abstract: The invention provides improved methods and systems for storing, sharing retrieving, writing and accessing data (content) on a blockchain. The invention may form part of a protocol for storing, searching and accessing the data. An embodiment of the invention comprises the step of processing at least one blockchain transaction (Tx) comprising: a protocol flag; a discretionary public key (DPK); and a discretionary transaction ID (DTx ID). These are discretionary in the sense that they are not required as part of the underlying blockchain protocol but in accordance with the present invention. This combination of features enables portions of data to be identified, retrieved and shared on a blockchain, and also to be linked/associated with one another when provided in a plurality of transactions. It enables a graph or tree-like structure to be constructed, which reflects the hierarchical relationships between portions of data, facilitating their processing, searching and sharing.

Abstract: A computer-implemented method of providing proof that a data item of a blockchain transaction exists on a blockchain, wherein the method comprises: obtaining, from a requesting party, target data item of a target blockchain transaction; obtaining the target blockchain transaction; obtaining a target Merkle proof for the target blockchain transaction, wherein a corresponding target Merkle root is contained within a block of the blockchain, and wherein obtaining the target Merkle proof comprises calculating an index of a target transaction identifier of the target blockchain transaction within a leaf layer of a corresponding target Merkle tree; and outputting at least the target Merkle proof for use by the requesting party as proof that the target data item exists as part of the target blockchain transaction on the blockchain.

Abstract: The disclosure provides improved methods and systems for processing, storing, sharing, retrieving, writing and accessing data (content) on a blockchain e.g. Bitcoin. The invention may form part of a protocol for storing, searching and accessing the data. In particular, improved efficiency and also enhanced access control permissions are provided. An embodiment of the disclosure comprises the step of processing at least one blockchain transaction (Tx) comprising: a protocol flag; a discretionary public key (DPK); and a discretionary transaction ID (DTxID). These are discretionary in the sense that they are not required as part of the underlying blockchain protocol but in accordance with the present invention. This combination of features enables portions of data to be identified, retrieved and shared on a blockchain, and also to be linked/associated with one another when provided in a plurality of transactions.

Abstract: The invention provides improved methods and corresponding systems for the sharing, storage, creation and accessing of data stored on a blockchain eg the Bitcoin blockchain. It may form part of a protocol for searching the blockchain for content/data. A method in accordance with the invention may be used for associating or linking data stored within (separate/different) blockchain transactions to enable the identification, retrieval and/or sharing of data stored therein. Additionally, or alternatively, it facilitates identification of transactions (TX) in a blockchain which store content/data that needs to be shared, transmitted, stored and/or accessed by a user. Such a method comprises the step of mapping a mnemonic to: 1) a public key (PK) associated with the transaction (TX); and 2) the transaction ID (TXID) of the transaction (TX).

Abstract: A computer-implemented method of generating a provable task for recording to a blockchain, the provable task for verifying (n+1) data items. A task blockchain transaction is generated, comprising a first locking script comprising (n+1) subscripts, each respective subscript defining a different unlocking condition corresponding to a knowledge proof, each unlocking condition being satisfied by a different one of a sequence of (n+1) verification values ri, the verification value r; being derived from (i+1) data values.

Abstract: A method performed in a system comprising a first party and a second party, the method comprising: generating, by the first party, a template of a first transaction having an input based on an output from a prior transaction associated with the second party; generating, by the first party, a message based on the template of the first transaction; generating, by the first party, a secret based on the message; generating, by the first party, a value based on the secret, wherein the secret cannot be derived from the value; generating, by the first party, a first puzzle transaction, wherein a first locking script of the first puzzle transaction comprises a knowledge proof configured to require an unlocking script to comprise the secret; publishing, by the first party, the first puzzle transaction to a first blockchain; obtaining, by the second party, the value based on the secret; signing, by the second party, the value based on the secret to create a signature; sending the signature from the second party to the

Abstract: The invention provides improved verification solutions for blockchain-implemented transfers. It is suited for, but not limited to, implementation in an SPV wallet. In accordance with one embodiment, a system or resource is provided which comprises a plurality of novel SPV verification components, the activities of which are coordinated by a coordination component. The system enables Bob to send Alice a payment transaction template (template Tx3) and requests: the full transaction data for all input transactions (Tx1, Tx2) comprising at least one output that Alice wants to spend as inputs to a transfer (Tx3); the Merkle path for all input transactions (Tx1, Tx2) linking them to their respective Merkle roots associated with their respective block headers; the completed transfer transaction (Tx3). Alice provides this information plus her signature.

Abstract: A computer-implemented method of executing a script formed from a locking script of a first blockchain transaction and an unlocking script of a second blockchain transaction, wherein the script comprises a first script portion, a version function, and a second script portion, and wherein the method comprises: a native script engine executing the first script portion; upon encountering the version function, the native script engine terminating execution of the script and determining whether the first script portion is valid according to a blockchain protocol; in response to determining that the first script portion is valid, the native script engine supplying a sub-script comprising at least the version function and the second script portion to a versioned script engine; and the versioned script engine executing the sub-script, wherein the execution of the sub-script by the versioned script engine does not affect the validity of the first and/or second blockchain transactions.

Abstract: Techniques are presented for securely transmitting a output script or information associated with a payroll and a user between a first node and a second node. The method comprises: determining a symmetric-key based on a common secret, based on a first node second private key and a second node second private key, wherein the second node has the same common secret based on a first node second public key and a second node second private key; encrypting at least part of the output script or information associated with the payroll and the second node with the symmetric-key, to an encrypted output script or encrypted information associated with the payroll and the second node; and sending the encrypted output script or encrypted information associated from the first node to the second node.

Abstract: A computer-implemented method (100) and system (1) for controlling the performance of a smart contract. The method includes storing a contract on or in a computer-based repository. The contract is associated with a licence between a first user (U1) and a second user (U2). The method further includes receiving, over a communications network, a transaction comprising a transfer of a token from an agent (A) to the first user (U1) or the second user (U2). The transaction comprises metadata that includes an identifier indicative of a location where the contract is stored. The method further includes querying a peer-to-peer distributed ledger (i.e. blockchain) to determine whether the transaction comprises at least one unspent output (UTXO). The method further includes, responsive to querying the peer-to-peer distributed ledger, determining whether to modify performance of the contract. The blockchain may be the Bitcoin blockchain.

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: Methods and system of recording work history of a mining node on a blockchain in a blockchain network. The methods may include mining a first block containing a registration generation transaction that includes, within a registration information field, a miner identifier for the mining node; and mining two or more additional blocks in an order, each additional block containing a generation transaction that includes an information field containing the miner identifier, a reference to the generation transaction of the preceding additional block in the order, wherein the registration generation transaction is a first block in the order. Work history may be verified by tracing the recorded work history and validating the miner identifier. Recorded work history may serve as the basis for a reputation score for the miner, which reflects contributed work evidenced by the proof-of-work secured work history.

Abstract: A computer-implemented method for granting permission to a requestor to join a first network. The first network comprises a set of bridging nodes and a set of devices controllable by one or more of the set of bridging nodes. Each bridging node is also a respective node of a blockchain network. The method is performed by a registration authority and comprises generating a first blockchain transaction. The first blockchain transaction comprises an input comprising a signature linked to a first public key of the registration authority. The first blockchain transaction also comprises a first output comprising a first certificate, the first certificate comprising an identifier assigned to the requestor. The method further comprises transmitting the first blockchain transaction to the blockchain network for inclusion in the blockchain.