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: Techniques are presented for the implementation of automated processes, such as device/system control, process control, distributed computing and storage, and 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. A counting solution is presented 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.

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: Methods and devices to enable the splitting of storage and validation functions from mining function in a blockchain network. The storage and validation nodes create candidate blocks and collect block rewards from successfully mined blocks. The mining nodes provide hash power for mining the candidate blocks and received resources from the storage and validation node for successful mining of a candidate block. Atomic exchange mechanisms are described for preventing loss and fraud and minimizing the use of bandwidth by mining nodes.

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 (?) 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 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: 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: 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 blockchain network may be used to improve upon public-key infrastructure by providing for fast and secure registration, revocation and update of digital certificates. A public key may be recorded on the blockchain by a certificate authority in such a manner that any third party may quickly and easily verify that the public key is certified by the certificate authority and that the certification has not been revoked. The certificate authority may be able to revoke the certification nearly instantaneously, and/or may be able to simultaneously certify a new key for the same entity while revoking the old key. In some cases, the ability to revoke a certification may be given to the owner of the public key or, in some cases, to one or even a group of other entities.

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: 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 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: 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 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: 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: 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