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: The present disclosure relates to highly secure, high speed encryption methodologies suitable for applications such as media streaming, streamed virtual private network (VPN) services, large file transfers and the like. For example, encryption methodologies as described herein can provide stream ciphers for streaming data from, for example, a media service provider to a plurality of users. Certain configurations provide wire speed single use encryption. The methodologies as described herein are suited for use with blockchain (e.g. Bitcoin) technologies.

Abstract: A method and system are disclosed for a computing resource to oversee handling and execution of a looping process, comprising: the computing resource monitoring a state of the blockchain to cause one or more transactions to be written to a blockchain, wherein execution of the looping process comprises the computing resource managing and running a loop, the loop having an index representing a current iteration and a limit indicating a total number of iterations of the loop, wherein an iteration of the loop comprises: incrementing the index by one, and executing a code block of the loop containing an if condition then action statement; storing the cryptographic hash in a blockchain transaction and broadcasting the blockchain transaction to the blockchain network to record the execution of the iteration of the loop; and repeating the loop steps until the limit is reached.

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: In one aspect, the present disclosure proposes methods, devices and systems and devices for providing a new structured data pertaining to blockchain transactions to implement a new data structure. This new data structure is provided to implement a distributed database. In another aspect, a new distributed data management system (DBMS) is provided, that can manage data associated with the new data structure. However, unlike a conventional DBMS for traditional databases, the present disclosure provides a blockchain DBMS that is configured to managed data associated with one or more blockchain transactions, said data being stored in the new data structure. In another aspect, the present disclosure provides a method for generating or providing one or more blockchain transactions for implementing one or more standard database commands that are received for accessing or manipulating a database, where the data is stored on the new data structure.

Abstract: A computer implemented system and a method for providing user related data, such as reputational information, on users of a blockchain involved in transactions is detailed. The method includes an approach for evaluating fulfilment of transactions, particularly in the context of contracts, and then providing a record of that on the blockchain through reputational information. As a result, at a late time, this reputational information can be retrieved. Similar reputational information for other transactions can be retrieved and linked to the same user, for instance based on the use of a hash of the master public key for a user. Aggregate reputational information can be computed from the pieces of reputational information retrieved.

Abstract: A method and corresponding system is presented for controlling a blockchain transaction output and/or specifying the recipient of the output. It also provides a method of controlling and/or generating an electronic communication. The unlocking script is provided in order to spend an output from a further transaction (Tx2) on the blockchain. The input of the transaction (Tx1) and/or the output of the further transaction (Tx2) may be associated with a tokenised asset represented on, or referenced via, the blockchain. The notification address may be associated with an asset or resource represented on the blockchain, or a controller of an asset or resource represented on the blockchain. The notification address may be a network address, a cryptographic key, a uniform resource locator (URI), email address or any other address or identifier which can be represented in the metadata of a transaction script and used as a destination for an electronic communication.

Abstract: Embodiments provide verification methods and systems for use in respect of data-oriented blockchain applications. In contrast to conventional signature verification in blockchain protocols, embodiments disclosed herein are performed in-situ within a single transaction, using only data that is provided within that transaction. Therefore, there is no reliance upon signatures provided from other transactions, and potential exploits such as replay attacks can be prevented. In an embodiment, this can be achieved by placing the signature in the output of the transaction rather than the locking script.

Abstract: A computer-implemented method and system are provided that provides functionality of a portion of source code, written in a high-level language (HILL), on a blockchain platform. The method and system comprise the steps of receiving a portion of source code as input, wherein the portion of source code is written in a high-level language, HILL; and generating an output script comprising a plurality of op_codes selected from and/or native to a blockchain scripting language such that, when executed, the output script provides, at least in part, a functionality specified in the portion of source code, the blockchain scripting language restricted from supporting recursive programming constructs.

Abstract: A specialized network (“merchant”) node to facilitate fast distribution of blockchain transactions over a network of interconnected nodes, as subset of which are merchant nodes interconnected by an overlay network. The merchant node includes a memory storing an assigned portion of a distributed mempool structured as a distributed hash table, the distributed mempool containing pending transactions awaiting confirmation. The merchant node operates by receiving a transaction, including a transaction identifier; hashing the new transaction identifier to obtain a key; determining, using the key, whether the transaction is stored in the distributed mempool or not and, if not, then storing the transaction in the distributed mempool as a pending transaction; and sending the transaction to a set of nodes other than merchant nodes using peer-to-peer connections. The invention may be used in conjunction with the Bitcoin blockchain or an alternative.

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: 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 for participating in a blockchain-based data record distribution process which includes multiple input addresses for input nodes and multiple output addresses for output nodes. One or more input nodes of the group of input nodes perform steps of: collaborating to determine a stealth address, forming a first transaction that pools data records to be transferred to the stealth address, and transmitting the first transaction to be validated and incorporated into the blockchain. One or more output nodes of the group of output nodes perform steps of: searching the blockchain to find the first transaction, identifying the stealth address, forming a second transaction that distributes pooled data records, collaborating via a threshold signature scheme to sign the second transaction, and transmitting the second transaction to be validated and incorporated into the blockchain. The invention may be used in conjunction with any blockchain implementation.

Abstract: Embodiments of the present disclosure provides protocols, methods and systems which provides advantages such as the resistance of centralisation of mining on a blockchain network, preferably a Proof-of-Work blockchain. A method in accordance with an embodiment may comprise generating a plurality of non-parallelisable challenges (or “puzzles”) and allocating one of said plurality of challenges to each miner on the network. The miner uses an inherently sequential (non-parallelisable) algorithm to find a solution to his allocated challenge. The challenges are generated by a committee of nodes, and a new set of challenges is generated for each block.

Abstract: A computer-implemented method of distributing a shared secret on a blockchain network. The method comprises mapping a plurality of inputs to elliptic curve points of an elliptic curve of an elliptic curve cryptography system. In a first encryption step, a plurality of the elliptic curve points are encrypted by a public key of a public-private key pair and decryptable by the corresponding private key of the public-private key pair. In a second encryption step, a plurality of parts of one input to a second encryption step are multiplied by terms of a series known to participants. In a secret sharing step, a plurality of shares of an input to a secret sharing step are distributed to a plurality of said participants, and an input is accessible to a threshold number of shares and is inaccessible to less than a threshold number of shares.

Abstract: The invention comprises a solution for securing an output (UTXO) in a single blockchain (e.g. Bitcoin) transaction (TX) so that it can only be unlocked by an authorised party at an allowed time, and in accordance with external data supplied to the transaction's locking script. The invention may comprise two steps which are implemented within a redeem script provided within the UTXO's locking script: 1) Calculation of a time-related value (which we will call Tsupplied) using the external data provided; and 2) use of the calculated Tsupplied value in a time lock technique to ensure that unlocking occurs at a time pre-determined time. The invention allows external data to be introduced into the time lock control of a transaction on the blockchain. It also includes a technique for combining absolute and relative time locks (e.g. CLTV and CSV as known in the Bitcoin protocol).

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 nLockTime+CheckLockTimeVerify (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: According to a first aspect disclosed herein there is provide a device comprising: a PUF module, and one or more outer layer components providing at least part of an unsecured channel for inputting a challenge to the PUF module and receiving back a response. Internal logic of the PUF module comprises a logging mechanism arranged to automatically log a record of the challenge and/or response in a log medium, e.g. a blockchain. According to a second aspect, there is provided a method comprising: sending a first message to be recorded on a blockchain, submitting a query to check that the first message has been recorded on the blockchain without manipulation, on condition thereof, sending a second messaging transaction to be recorded on the blockchain. The first and second aspects may be used together or independently.

Abstract: According to a first aspect of the disclosure, there is provided a request-response protocol for requesting access to data from a destination transaction. According to a second aspect of the disclosure, there is provided a method of accessing data from one or more destination transactions stored on a blockchain, wherein the method comprises selecting one or more hyperlinks linking to the destination transaction(s).

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.