Abstract: The present disclosure relates to a computer implemented method for verifying a blockchain stored representation of a dataset. The method comprises the steps of obtaining a dataset reference to an on-chain dataset, the on-chain dataset being stored on the blockchain and comprising data carrying transactions, wherein each data carrying transaction comprises data indicative of an event stored in an off-chain dataset. The method includes traversing the on-chain dataset and for each data carrying transaction in the on-chain dataset: determining that the data indicative of an event in the off-chain data set is associated with an event in the off-chain dataset, and verifying that the on-chain dataset and the off-chain dataset correspond to each other.

Abstract: There is provided a computer implemented method. The method provides a generation of a proof of existence data structures. The method comprising: (i) receiving a request comprising a data reveal path, the data reveal path referencing a node of interest within an input hierarchical data structure (ii) obtaining the input hierarchical data structure comprising an input root node and a plurality of input nodes, wherein each of the input nodes within the input hierarchical data structure have an associated value, and (iii) generating an output hierarchical data structure based on the data reveal path and the input hierarchical data structure, wherein the output hierarchical data structure comprises a plurality of output nodes. There is also provided a method for verification of the proof of existence.

Abstract: A computer-implemented method of generating a share of a shared private key, wherein each participant of a group of participants has a respective share of a master private key, and wherein the method is performed by a first participant of the group and comprises: generating a first share of a first shared secret, wherein each other participant of the group generates a respective share of the first shared secret; and generating a first share of a first shared private key based on a first share of the master private key and the first share of the first shared secret.

Abstract: A method of proving that a secret committed in a commitment is a discrete logarithm of a public element of a finite group of data elements, comprising: obtaining a first vector used to generate the commitment, the first vector comprising n components, wherein one of the n components of the first vector is at a position which corresponds to the secret; generating a second vector comprising n components, wherein a component of the second vector, at a predetermined position corresponding to the position in the first vector, is set to zero; generating a further commitment to the second vector; transmitting the further commitment to a verifying device; receiving a random challenge from the verifying device; generating a response using the first vector, the second vector and the random challenge; and transmitting the response to the verifying device to prove that the secret is the discrete logarithm of the public element.

Abstract: The present disclosure proposes methods, devices and systems for synchronising a plurality of event streams using an atomic blockchain transaction, the transaction having multiple inputs, each spending a dust output of a previous transaction for a respective event stream among the plurality, each input having an unspent dust output and a data payload.

Abstract: A method is provided by which payments for assets are recorded using blockchain transactions, and verified based on immutable logs associated with the transactions.

Abstract: Methods and systems for compressing transaction identifiers by a mining node in a blockchain network. The method may include receiving transaction data regarding a blockchain transaction having a transaction identifier; appending the transaction identifier to a global transaction identifier list at a position associated with an index; generating a fixed-length prefix value from the transaction identifier using a function, wherein the function has an equiprobable distribution of results across a range of fixed-length prefix values; identifying a memory location associated with the fixed-length prefix value and storing the index in a data structure at the memory location; truncating the transaction identifier to a shortened transaction identifier; and outputting the fixed-length prefix value concatenated with the shorted transaction identifier as a compressed transaction identifier.

Abstract: Blockchain transactions are created to implement the functionality of a logic gate. Implementation may be on the Bitcoin platform or an alternative blockchain platform. The transaction includes a locking script which comprises instructions selected so as to implement the functionality of a logic gate such as the XOR gate. When the script is executed (because a second transaction is attempting to spend the output associated with the locking script) the inputs will be processed by the conditional instructions to provide an output of TRUE or FALSE. The second transaction is transmitted to the blockchain network for validation and, if determined to be valid, it will be written to the blockchain. Validation of the second transaction can be interpreted as a TRUE output. Thus, the locking script of the first transaction provides the functionality of the desired logic gate.

Abstract: A computer-implemented method of enforcing conditions on a second blockchain transaction using a first blockchain transaction, wherein a first one of the conditions is that, when a first unlocking script of the second transaction is executed alongside a first locking script of the first transaction, a representation of the second transaction is output to memory, wherein the representation is based on a plurality of fields of the second transaction and a first output of the first transaction, and wherein the method comprises: generating the first transaction, wherein the first transaction comprises a first output, wherein the first output comprises the first locking script, and wherein the first locking script comprises: a message sub-script; a signature sub-script; a public key corresponding to a private key; and a verification sub-script.

Abstract: The present disclosure provides methods and systems for distributed and/or parallel processing of data records, and in particular mining of blockchain transactions in a blockchain block, and further still for generation of a Proof-of-Work (PoW) for a blockchain block. Advantageously, embodiments allow for separation of the PoW calculation from other blockchain mining/validation tasks. Preferably, a PoW requester sends a specialist PoW provider one or more of: i) a Merkle root for a Merkle tree that represents a set of transactions ii) a control transaction (TX0) and iii) a Merkle proof which confirms that TX0 is included in the set of transactions. TX0 may provide or comprise control data that the PoW provider can use to determine whether or not performance of the PoW calculation is to be performed or completed.

Abstract: A computer-implemented method for revoking access to a first network, wherein 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, wherein each bridging node is also a respective node of a blockchain network, and wherein each bridging node and device is associated with a respective certificate granting access to the first network; the method being performed by a registration authority and comprising: obtaining an alert transaction, the alert transaction being a blockchain transaction and comprising a first output, the first output comprising an alert message identifying one or more bridging nodes and/or one or more devices; and revoking access to the first network by the identified one or more bridging nodes and/or one or more devices by revoking the respective certificate of the identified one or more bridging nodes and/or one or more devices.

Abstract: An event detecting, monitoring and/or counting mechanism is disclosed. The event may be, for example, a vote, decision or selection which is made by a given entity. A counting solution is provided in which a computing resource, running simultaneously and in parallel to a 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. If the computing resource finds a transaction which contains a hash relating to the loop it accesses the relevant portion of code.

Abstract: A computer-implemented method of generating shares of private keys, wherein the method is performed by a first participant of a group of participants and comprises: obtaining a first seed share, wherein each other participant has a respective seed share; generating a first master private key share of a shared master private key, wherein the first master private key share is generated based on the first seed share and the respective seed share of each other participant, and wherein each other participant has a respective master private key share; and generating one or more first private key shares based on the first master private key share, wherein each first private key share is a share of a respective shared private key.

Abstract: The invention provides a novel and advantageous method and corresponding system. The invention is implemented via a distributed electronic ledge (blockchain). This may or may not be the Bitcoin blockchain. The invention is suited for the exchange or transfer of an asset, e.g. a digital asset, such as tickets and the like (but not limited in this regard).

Abstract: A method performed in a layered network. The layered network comprises a core layer comprising one or more core nodes, one or more intermediate layers each comprising one or more intermediate layer nodes, and one or more outer layers each comprising one or more outer layer nodes. Each of the core nodes is a node of a blockchain network. One or more intermediate layer nodes are smart contracts nodes providing a smart contract service for maintaining the state of a smart contract. One or more outer layer nodes are client nodes of the smart contract service. The method included, by a smart contract node: recording a state of the smart contract in a record of the state maintained at the first smart contract node. In addition, at least a first transaction also recording the state is recorded on a blockchain of the blockchain network.

Abstract: The invention relates to distributed ledge technologies such as consensus-based blockchains. Computer-implemented methods for a secure random number generation within blockchain scripts are described. The invention is implemented using a blockchain network, which may be, for example, a Bitcoin blockchain. A third transaction is validated. The third transaction is associated with a third digital asset and includes a first and second puzzle in a locking script. The first puzzle is included, in a first transaction, in a first locking script that encumbers transfer of control of a first digital. The second puzzle is included, in a second transaction, in a second locking script that encumbers transfer of control of a second digital asset. A pseudorandom number is generated based at least in part on solutions to the first and second puzzles. Control of the third digital asset is transferred based at least in part on the pseudorandom number.

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: Systems and methods described herein relate to the execution of locking transactions in a blockchain system. In the context of smart contracts, it may be advantageous to have a public record (e.g., recorded on a blockchain) of a proof of correct execution of a circuit published by a worker and the verification key, thereby allowing anyone (e.g., nodes of the blockchain) to verify validity of the computation and proof. However, there are challenges to recording large blocks of data (e.g., large keys that may comprise multiple elliptic curve points) on the blockchain. For example, in a Bitcoin-based blockchain network, a protocol that utilizes standard transactions may be constrained to locking scripts and unlocking scripts that are collectively no t larger than a first predetermined size limit, and the size of a redeem script (if utilized) may be limited to being no more than a second predetermined size limit.

Abstract: A computer-implemented method of representing a first set of data items, wherein the method is performed by a first tree generator and comprises: allocating the first set of data items into a plurality of respective subsets; for each respective subset of data items, generating a respective hash tree based on the respective subset of data items, wherein the respective hash tree comprises a respective root node; and generating a respective first hash set representing the first set of data items, wherein the first hash set comprises each of the respective root nodes.

Abstract: A computer-implemented method of generating blockchain transactions, wherein the method is performed by a first party and comprises: generating a first blockchain transaction, wherein the first blockchain transaction comprises a first compact script (CS), wherein the first CS is at least partly written in a high-level (HL) scripting language and comprises one or more HL functions, wherein when executed, each HL function is configured to perform an operation equivalent to a respective operation performed by one or more low-level (LL) functions of a LL scripting language, wherein the first CS is configured to perform an operation equivalent to a first expanded script (ES) written in the LL scripting language and comprising a plurality of LL functions, and wherein the first CS is smaller in storage size than the first ES; and making the first blockchain transaction available to one or more nodes of a blockchain network and/or a second party.