Abstract: In a first aspect, the present disclosure proposes computer implemented methods, devices, and systems for implementing a channel service for messages or transactions that are associated with a blockchain, the channel service being provided for one or more clients. The method comprising providing a given client access to one or more functions that enable direct communication between the given client and another entity, the one or more functions include (i) channel functions or procedures pertaining to one or more channels for transmission of data; and/or (ii) message functions or procedures pertaining to the data being transmitted using the one or more channels. In a second aspect, the present disclosure proposes computer implemented methods, devices, and systems for implementing addressing for a channel service, such as the channel service in the first aspect. Communication using a channel associated with the channel service is initiated based on the addressing keys pertaining to the communicating entities.

Abstract: Methods and devices for propagating blocks in a blockchain network. At a mining node, while hashing a first block header of a first candidate block, the mining node sends, to other mining nodes, a first message specifying transactions and their order in a first ordered set of transactions contained in the first candidate block. The mining also receives a second message specifying transactions and their order in a second ordered set of transactions contained in a second candidate block being mined by a second mining node. If the mining node succeeds in mining the candidate block it notifies other mining nodes by providing them with a coinbase transaction, hash value, and timestamp. If another mining node is successful, then the mining node receives information from the other mining node from which, in conjunction with the second message, it can assemble the second candidate block and validate it.

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 of verifying the integrity of part of a pre-image corresponding to a hash digest generated by hashing the preimage with a SHA-based hash function, wherein the pre-image comprises a first message and a second message, and wherein the method comprises: a) receiving an iteration input vector; b) obtaining a second sequence of blocks; c) generating a final iteration output vector by performing an iteration of the SHA-based hash computation for each of the second sequence of blocks in order of a respective position in the second sequence of blocks, wherein the iteration of the SHA-based hash computation performed on a first one of the second sequence of blocks is based on the obtained iteration input vector; and d) generating a candidate hash digest based on the final iteration output vector, the candidate hash digest being for comparison with the hash digest.

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: Embodiments provide improved solutions for verifying one or more tokens provided via a token transaction on a blockchain. The token transaction is generated by an issuer and forms a link in a chain of token transactions which can be traced back to a minting transaction that was used by the issuer to generate the token(s). At least one certification element is provided in one or more token transactions within the chain, wherein the certification element certifies the authenticity of the token(s) by or on behalf of the issuer. A validating entity need only traverse the token's history chain back to a transaction which comprises a certification element rather than back to the mint transaction. Additionally, or alternatively, the disclosure provides improved solutions for melting and reminting the token when a pre-determined threshold, limit or specified value has been reached.

Abstract: A method of enforcing a locking script to be propagated throughout a chain of blockchain transactions. The method comprises generating a primary transaction comprising a primary locking script configured to, when executed by an unlocking script of an auxiliary transaction, verify that the unlocking script comprises a message generated based on the auxiliary transaction, and verify, based on the message, that an output of the auxiliary transaction comprises an auxiliary locking script. The auxiliary locking script is configured to verify that an unlocking script of a second primary transaction comprises a message generated based on the second primary transaction, verify that the unlocking script of the second primary transaction comprises a data item comprising one or more locking scripts of the primary transaction, and verify, based on the message and the data item, that an output of the second primary transaction comprises the primary locking script.

Abstract: Methods and devices for resolving a collision in short transaction identifiers in a blockchain network. The method may include receiving a set of short transaction identifiers from a sending node. The receiving node locates a corresponding full transaction identifier for each short transaction identifier in a mempool. For at least one short transaction identifier, the receiver identifies a collision. It then sends a message to the sending node requesting resolution of the collision regarding the at least one short transaction identifier, and receives collision resolution data from the sending node to enable identification of a valid corresponding full transaction identifier for the at least one short transaction identifier. The receiver may send intermediate Merkle tree hashes with its request for resolution, and the collision resolution data may include information identifying which of the hashes is incorrect.

Abstract: Methods and systems to control mining pools configured to mine more than one blockchain network. A pool controller may automatically select a candidate block generated for one of the blockchain networks for mining by the mining units. The selection may be based on determining an expectation value associated with each current candidate block generated for the respective blockchain networks and which of them is the highest. The expectation value may be based, at least in part, on a current coinbase value and a current difficulty setting for that blockchain network. The pool control may perform the selection with the generation of each new candidate block for any of the blockchain networks.

Abstract: Methods and devices for resolving a collision in short transaction identifiers in a blockchain network. The method may include receiving a set of short transaction identifiers from a sending node. The receiving node locates a corresponding full transaction identifier for each short transaction identifier in a mempool. For at least one short transaction identifier, the receiver identifies a collision. It then sends a message to the sending node requesting resolution of the collision regarding the at least one short transaction identifier, and receives collision resolution data from the sending node to enable identification of a valid corresponding full transaction identifier for the at least one short transaction identifier. The receiver may send intermediate Merkle tree hashes with its request for resolution, and the collision resolution data may include information identifying which of the hashes is incorrect.

Abstract: Methods and computing devices for consolidating tokens in a token system. The method may include receiving an instruction to consolidate two or more serialized tokens, each token having a respective serial number that includes a root identifier, a denomination code, and a leaf identifier allocated to that denomination code. The tokens are of denominations that, when summed, equate to a larger denomination. The method may include identifying a candidate root identifier and candidate leaf identifier, wherein the candidate leaf identifier is allocated to the larger denomination; determining that the candidate root identifier and the candidate leaf identifier are available for use; generating a new token having a new serial number containing the candidate root identifier, the candidate leaf identifier, and a denomination code corresponding to the larger denomination; and notifying an issuer computing device of consolidation and deactivation of the two or more serialized tokens resulting in the new token.

Abstract: Methods and devices for splitting serialized tokens. The method may be triggered by receiving an instruction to transfer a selected denomination token to a second computing device. The method may include identifying a first token having a first denomination larger than the selected denomination, with a first serial number formed from a first denomination code, a unique root identifier, and a leaf identifier uniquely identifying a path of division from the unique root identifier to the first denomination in a root denomination tree. It may then include splitting the first token by generating a second serial number for a second token by concatenating a second denomination code for the selected denomination, the unique root identifier, and an extended leaf identifier, wherein the extended leaf identifier uniquely identifies a further path of division from the first denomination to the selected denomination in the root denomination tree.

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.

Abstract: Methods and devices for compressing transaction identifiers by a first mining node in a blockchain network. The method may include building a first candidate block containing a first ordered list of transaction identifiers; receiving, from a second mining node, data defining a second ordered list of transaction identifiers in a second candidate block being mined by the second mining node; determining that at least one of the transaction identifiers in the first ordered list is also in the second ordered list; generating an append message containing data defining the first ordered list of transaction identifiers, wherein the data specifies said at least one transaction identifier in the first ordered list of transaction identifiers by including an index position of said at least one transaction identifier in the second ordered list of transaction identifiers; and transmitting the append message to the second mining node.

Abstract: Candidate block data is pre-propagated using append messages such that each miner builds append only lists representing the candidate blocks being worked on by those other miners. The append only lists can end up out-of-sync with earlier versions of a candidate block being worked on by mining units at a miner. A block finalize message may be received providing a block solution for a final candidate block and including synchronization data. The synchronization data details one or more transactions appended to the append only list associated with the winning miner are not included in the final candidate block for which the block solution was found, enabling the receiving miner to remove those one or more transactions from the append only list associated with the winning miner to produce a final append only list and construct and validate a solved block from the final append only list.

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: Methods and systems to control mining pools configured to mine more than one blockchain network. A pool controller may automatically select a candidate block generated for one of the blockchain networks for mining by the mining units. The selection may be based on determining an expectation value associated with each current candidate block generated for the respective blockchain networks and which of them is the highest. The expectation value may be based, at least in part, on a current coinbase value and a current difficulty setting for that blockchain network. The pool control may perform the selection with the generation of each new candidate block for any of the blockchain networks.

Abstract: Methods, devices, and a data structure for signalling Merkle proof data that includes an index position field for the position of the transaction within the ordered set of transactions within the block. The index enables computationally straight-forward determination of the left-hand/right-hand location of each calculated element when bottom-up tracing a Merkle path. Methods and devices for performing a Merkle proof using the index include at least one extended validity check within the Merkle proof process. In some instances, the extended validity check enables validation of transaction count for a block and/or a proof of index validity.

Abstract: Methods and systems for relaying double-spend transactions in a blockchain network. A mining node that detects a potential double-spend may send a notification regarding the attempt. Nodes in the network may retrieve transaction data regarding the two transactions involved and verify whether the double-spend identified in the notification is valid or not. The notification may be signed by the mining node using a miner ID, and invalid notifications may have negative impact on an associated reputation score in some cases. A repudiation notice may be generated by a node that determines that a double-spend notification is invalid.

Abstract: Methods and systems to control mining pools configured to mine more than one blockchain network. A pool controller may automatically select a candidate block generated for one of the blockchain networks for mining by the mining units. The selection may be based on determining an expectation value associated with each current candidate block generated for the respective blockchain networks and which of them is the highest. The expectation value may be based, at least in part, on a current coinbase value and a current difficulty setting for that blockchain network. The pool control may perform the selection with the generation of each new candidate block for any of the blockchain networks.