Abstract: A computer-implemented method of alerting users to on-chain events, wherein a primary user is associated with a primary user public key, and wherein the method is performed by an alerting entity and comprises: identifying one or more event transactions, wherein each event transaction comprising respective event data; generating a primary alert transaction, wherein the primary alert transaction comprises a first output locked to the primary user public key, and a second output comprising alert data, and wherein the alert data comprises a respective identifier of each identified event transaction; and transmitting the primary alert transaction to the blockchain network.

Abstract: A computer-implemented method of executing blockchain transactions, wherein a first blockchain transaction comprises a first output, wherein the first output comprises a first locking script comprising a version opcode, wherein a second transaction comprises a first input that references the first output of the first transaction and comprises a first unlocking script, and wherein the method is performed by a blockchain node and comprises: executing the first locking script together with the first unlocking script, wherein said execution comprises, upon executing the version opcode, obtaining a node protocol version number of the blockchain node, and outputting the node protocol version number, wherein the node protocol version number is associated with a particular functionality that the blockchain node is configured to execute.

Abstract: A computer-implemented method of deriving keys of a hierarchical key structure, wherein the method is performed by a first party and comprises: generating a target index of a target child key, wherein the target index is generated based on a first result of inputting at least a target message to a first hash function; and deriving the target child key of a level in a hierarchy of a key structure based on a) a parent key of a preceding level in the hierarchy, and b) a second result of inputting at least i) the parent key, and ii) the target index, to a second hash function.

Abstract: A computer-implemented method of transmitting blockchain transactions to a blockchain network, wherein the method is performed by a first party and comprises: transmitting at least part of a blockchain transaction to an internet server via an internet service hosted by the internet server, wherein the internet server is configured to connect to one or more nodes of the blockchain network, and to transmit a blockchain transaction to the one or more blockchain nodes, wherein the transmitted blockchain transaction comprises the at least part of the blockchain transaction.

Abstract: A computer-implemented method of pseudo-randomly selecting a data element using blockchain transactions, wherein the method is performed by a first party and comprises: obtaining an ordered list of data elements and a plurality of seed inputs; generating a first transaction; and causing the first transaction to be made available to one or more blockchain nodes for inclusion in the blockchain, wherein the first transaction comprises a first output script, and wherein when executed alongside an input script of a second transaction, the first output script is configured to: output a re-ordered list of the data elements; output a pseudorandom number generated based on the plurality of seed inputs; and output, as a selected data element, the data element positioned at a position in the re-ordered list of data elements corresponding to the pseudorandom number.

Abstract: A computer-implemented method of generating a blockchain address based on a corresponding template output script of a blockchain transaction, wherein the blockchain address comprises a prefix component and a data component, and wherein the method is performed by a first party and comprises: generating a first blockchain address based on a first template output script, the first blockchain address comprising a first prefix component for identifying a first template output script, and a first data component representing one or more data items required to populate the first template output script; wherein the first prefix component is greater than one byte, and/or wherein the first data component is generated based on a plurality of data items required to populate the first template output script.

Abstract: A computer-implemented method of accepting blockchain transactions, wherein the method is performed by a blockchain node of a blockchain network and comprises: generating a first transaction comprising a first output, the first output comprising a first output script; causing the first transaction to be published on the blockchain; receiving a second transaction comprising a second output, the second output comprising a second output script; and accepting the second transaction based on one or more conditions being met, wherein a first condition of said one or more conditions is that the second output script corresponds to the first output script.

Abstract: A system comprising a layered network, wherein the layered network comprises a plurality of LN nodes arranged in an ordered set of layers, the ordered set of layers comprising, in order, a core layer comprising a plurality of master nodes each connected to one or more blockchain nodes of a blockchain network, one or more intermediate layers comprising a respective set of intermediate nodes, and a device layer comprising a set of end devices, wherein: each master node is configured to control a respective subset of intermediate nodes; a first master node is configured to control a first subset of intermediate nodes; a second master node is configured to control a second subset of intermediate nodes; and each intermediate node is configured to control a respective subset of end devices.

Abstract: A computer-implemented method of testing whether or not a blockchain transaction is a double spend attempt, the method being performed by a first party and comprising: generating a first blockchain transaction, wherein the first blockchain transaction comprises an input for unlocking an output of a blockchain transaction previously transmitted to one or more nodes of a blockchain network for inclusion in the blockchain; generating a signature based on the first blockchain transaction and one or more time indicators, each time indicator indicating when the first blockchain transaction was generated and/or transmitted to a second party; and transmitting to the second party, the first blockchain transaction, the signature and the one or more time indicators, wherein at least the first blockchain transaction is transmitted to the second party via an off-chain communication channel.

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: A computer-implemented method of pseudo-randomly selecting game elements for use in playing a game. An oracle obtains: a set of seed data items, the set of seed data items comprises one or more user seed data items generated by a respective user; a sequence of public keys; and a list of game elements. A total number of public keys corresponds to a total number of game elements. The oracle generates a first output of a game transaction. The first output comprises the sequence of public keys and a script configured to generate at least one pseudorandom number based on the set of seed data items. The script is configured to generate a list of the public keys based on the at least one pseudorandom number. An order of public keys in the list of public keys differs compared to an order of public keys in the sequence of public keys.

Abstract: A computer-implemented method of pseudo-randomly generating winning game elements for use in playing a game. An oracle obtains: a set of seed data items, the set of seed data items comprising one or more user seed data items; and a sequence of first public keys, each first public key representing a respective one of the set of first game elements. The oracle generates an output of a game transaction that comprises an output script. The script comprises the sequence of at least some of the first public keys, and wherein the output script is configured to, when executed, generate at least one pseudorandom number, the pseudorandom number being based on the set of seed data items, and to select a winning key, the winning public key being the public key at a position in the sequence of first public keys corresponding to the pseudorandom number.

Abstract: A computer-implemented method of generating a transaction associated with a blockchain, the transaction being for distributing amounts of an allocation of a digital asset, wherein the allocating party is associated with an allocating public key linked with the allocation, and wherein each recipient party is associated with a respective ownership public key. The method comprises obtaining a respective ownership public key of each of the one or more recipient parties. For each of the one or more recipient parties, a respective payment public key is generated based on (i) the ownership public key associated with that recipient user, and (ii) the allocating public key. The transaction comprises one or more output scripts, each output script configured to transfer a respective amount of the allocation to a respective payment address, the respective payment address being based on the respective payment public key.

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.

Abstract: A computer-implemented method for controlling one or more devices of 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 node of a blockchain network, and each device has a respective device identifier. The method is performed by a first one of the bridging nodes and comprises generating a first blockchain transaction. The first blockchain transaction comprises a first input comprising a signature linked to a first public key of the first node, and a first output comprising command data. The command data comprises a respective identifier of a first one of the devices controlled by a second one of the bridging nodes, and a command message for controlling the first device.

Abstract: A method of executing a transaction of a blockchain. The transaction comprises at least one output comprising a locking script, and the locking script comprises an instance of a first opcode and one or more instances of a second opcode. Each instance of the second opcode separates portions of the locking script. Upon calling the instance of the first opcode, a first data element is read from at least one stack, the first data element being generated during execution of the locking script with an unlocking script of a different transaction. A first part of the locking script that follows an instance of the second opcode corresponding to the first data element is output.

Abstract: A method of executing transactions of a blockchain network. A first transaction comprises at least a first output comprising a first locking script of a stack-based scripting language, the first locking script comprising a portion of the first locking script to be executed before a first instance of an opcode is executed. A second transaction comprises a first unlocking script that references the first output in the first transaction. Upon executing the first instance of the opcode, execution of the first locking script is terminated whilst not invalidating the first transaction. A first data element is read from at least one stack, wherein the first data element is generated during execution of the first unlocking script and the portion of the first locking script. The first data element as read from the at least one stack is supplied to an off-chain function, wherein the function is configured to generate a result based on at least said first data element.

Abstract: A method of validating transactions for recordal in a blockchain comprises receiving one or more transactions at a node of a blockchain network. For each received transaction a protocol for validating the transaction is applied. The protocol is configured to allow a termination opcode to be included in an output script of the transaction. The termination opcode is configured to, upon being executed by the node, a) terminate execution of the output script, and b) not to invalidate the transaction based only on the inclusion of the termination opcode in the output script. The protocol is also configured to disallow any instance of the termination opcode from being included in an input script of the transaction, said disallowing comprising the node at least invalidating the transaction if any instance of the termination opcode is included in the input script.