Abstract: An operator for a global total order broadcast domain executing a method to send an operation out of band to nodes of participating parties in a partition, receive a certificate and a signature on the operation for each of the participating parties, generate a single party packet based on the received signatures, generate a random symmetric encryption key, send the random symmetric encryption key to the participating parties, encrypt the single party packet with the random symmetric encryption key, generate a pseudo random string for the partition, and record an operation identifier, the encrypted party packet, and the pseudo random string on the global total order broadcast domain.

Abstract: Disclosed herein are methods and systems for executing verifiable computation modules to process private data at private data owner platform, comprising obtaining a computation module having a unique identifier recorded in a distributed ledger controlled by a plurality of computing nodes, generating a key pair comprising a signing key and a verification key derived from the signing key, recording, in the distributed ledger, an execution record associating an execution instance of the computation module with the verification key, initiating the execution instance of the computation module to process a private dataset incorporated with the signing key. outputting a computation outcome, computing an execution result signature for the execution instance based on the unique identifier and the private data and the signing key, and recording the execution result signature in the distributed ledger to enable verification of the execution instance.

Abstract: An example operation may include one or more of receiving, by each of one or more peripheral peers of a blockchain network, a new block from an orderer peer, calculating a hash of the new block, determining the calculated hash is different than hashes from a majority of peripheral peers, determining that one or more blocks that correspond to the different hashes from the majority of peripheral peers are different from the new block, and in response ceasing committing blocks to the blockchain network.

Abstract: An example operation may include one or more of anonymizing, via an anonymization service hosted within a trusted execution environment (TEE), raw data provided by a computing node to generate anonymized data, generating, via the anonymization service, an authenticator object that binds together a hash of the raw data and a hash of the anonymized data, transmitting the generated anonymized data to the computing node, and submitting the authenticator object to a blockchain ledger via a blockchain transaction.

Abstract: An example operation may include one or more of receiving, by each of one or more peripheral peers of a blockchain network, a sequence of new blocks from an orderer peer, calculating hashes for the sequence of new blocks, adding the hashes to a merkle tree, determining the merkle tree is different than merkle trees from a majority of peripheral peers, determining that one or more blocks that correspond to the different merkle trees from the majority of peripheral peers are different from the sequence of new blocks, and in response ceasing committing blocks to the blockchain network.

Abstract: An example operation may include one or more of establishing a communication channel between a sending system and a receiving system, executing an oblivious transfer protocol between the sending system and the receiving system via the established communication channel, wherein the oblivious transfer protocol provides the receiving system with a functional encryption key based on a data vector of the receiving system without the sending system learning the data vector, committing to the functional encryption key using a cryptographic commitment and signing the functional encryption key commitment with a digital key of the receiving system, and storing the signed functional encryption key commitment to a blockchain.

Abstract: Recursive endorsements in a decentralized database minimize validation effort for a smart contract because there are fewer signatures to verify. Collected endorsements required by an endorsement policy are verified and signed by a set of trusted peers representing different organizations, the set of trusted peers being fewer than the number of endorsing peers. Prior to validation, the target transaction is submitted with all required endorsements and the signatures of the set of trusted peers. Validation is performed by verifying only the signatures of the set of trusted peers.

Abstract: Systems, methods, and computer programming products leveraging the use of machine learning, cryptographic keys and blockchain technology for validating blockchain transactions. The disclosed systems, methods and products improve detection of malicious cyberattacks and fraud, while reducing occurrences of falsely invalidated transactions and improving overall blockchain security in both permissioned and permissionless blockchain networks. Classifiers are trained using machine learning and other classification techniques by building a transaction history to learn how to identify suspicious transactions on the blockchain. In permissionless and order-execute models of permissioned blockchains, cryptographic keys are publicly registered to guardians residing out of band, who may co-sign requests and override or resubmit transactions marked as suspicious by the classifiers.

Abstract: An example operation may include one or more of encrypting content via an encryption key to generate encrypted content, storing the encrypted content via a distributed ledger, splitting the encrypted encryption key into a set of key shares via a threshold secret sharing scheme, and distributing the set of key shares among a plurality of nodes of a distributed vault, where each key share is distributed with an expiry value that identifies when the respective key share is to be deleted by a node.

Abstract: An example operation includes one or more of generating, by a channel peer, a random value to be associated with a channel name, mapping, by the channel peer, the random value to a block range, receiving, by the channel peer, a channel-MAC from a second peer, and validating the channel-MAC based on the channel name and the random value.

Abstract: An example operation includes one or more of receiving view change messages which request a view change from a previous primary peer of a blockchain to the primary peer, identifying that a change to a state of the blockchain is in process with the previous primary peer based on metadata of the received view change messages, verifying that the change to the state of the blockchain corresponds to a latest change to the blockchain based on a received view data message, and transmitting a new view message to following peers which includes the in-process change to the state of the blockchain.

Abstract: An example operation may include one or more of receiving, from a plurality of providers by a secure enclave, a plurality of training data sets and a plurality of salts paired with the plurality of training data sets, respectively, hashing, via the secure enclave, pairs of training data sets and salts to generate a plurality of salted hashes, and combining the plurality of salted hashes to generate a digest, training, via the secure enclave, a model based on the plurality of training data sets to generate a trained model, and providing the trained model and the digest to a plurality of data providers of the plurality of training data sets and the plurality of salts.

Abstract: Systems, methods, and computer programming products leveraging the use of machine learning, cryptographic keys and blockchain technology for validating blockchain transactions. The disclosed systems, methods and products improve detection of malicious cyberattacks and fraud, while reducing occurrences of falsely invalidated transactions and improving overall blockchain security in both permissioned and permissionless blockchain networks. Classifiers are trained using machine learning and other classification techniques by building a transaction history to learn how to identify suspicious transactions on the blockchain. In permissionless and order-execute models of permissioned blockchains, cryptographic keys are publicly registered to guardians residing out of band, who may co-sign requests and override or resubmit transactions marked as suspicious by the classifiers.

Abstract: An example operation includes one or more of receiving view change messages which request a view change from a previous primary peer of a blockchain to the primary peer, identifying that a change to a state of the blockchain is in process with the previous primary peer based on metadata of the received view change messages, verifying that the change to the state of the blockchain corresponds to a latest change to the blockchain based on a received view data message, and transmitting a new view message to following peers which includes the in-process change to the state of the blockchain.

Abstract: A node in a blockchain network generates a non-fungible token (NFT) and obtain docket information for the NFT comprising transfer conditions for the NFT. The node also generates a docket credential with embedded transfer terms for the NFT from the docket information as part of a signature scheme for the NFT and signs an NFT block on a blockchain network with the docket credential.

Abstract: A computer-implemented system and method process a private transaction for dividing a blockchain transaction into a plurality of requests. Each of the requests have transaction data and a same transaction identifier. Each request is sent to a respective participating shard of a set of participating shards in the blockchain transaction of the blockchain. A response to the request is received from each participating shard, and each of the responses is sent to at least the participating shards except the shard the response was received from. In an atomic commit operation, a prepare transaction is created comprising information from the responses and the transaction identifier. The prepare transaction is submitted to the blockchain, and validity answers are received from the shards.

Abstract: A method for providing privacy-preserving asset transfers between networks, by connecting to a first blockchain network, receiving login data from a user, receiving an asset pledge transaction for an asset, confirming that the user is an owner of the asset based on a previous asset transfer transaction associated with the user, verifying an availability of the asset based on first blockchain network records, determining that a recipient is a registered user of a second blockchain network, assigning the asset to a first unique identifier, receiving at least one of a pledge proof request, from the recipient prior to expiration of the deadline, and an asset reclaim transaction, from the user after expiration of the deadline, the pledge proof request and reclaim transaction each comprising the first unique identifier and responding to the at least one of the pledge proof request and the asset reclaim request according to the deadline.

Abstract: A method for documenting asset exchanges between users by connecting to a first blockchain network configured to store user assets, receiving login data from a first user, receiving an asset lock transaction for an asset from the first user, confirming that the first user is an owner of the asset based on a previous asset transfer transaction associated with the user, verifying availability of the asset based on blockchain network records, determining that the second user is a registered user of the blockchain network, assigning the asset to a unique identifier of the asset lock transaction, receiving at least one of a claim request from the second user, prior to expiration of the deadline, and a reclaim transaction from the user following expiration of the deadline, and responding to the at least one of the claim request and the reclaim request according to the deadline.

Abstract: A computer-implemented method for establishing consensus in a blockchain network, a total ordering service for a blockchain network, and a computer program product. One embodiment may comprise providing a first total ordering service (TOS) gateway for an organization in a blockchain network, generating a symmetric key at the first TOS gateway, splitting the symmetric key to generate a plurality of key shares, and distributing at least one of the plurality of key shares to a second TOS gateway in the blockchain network. The TOS gateway in some embodiments may have read/write access to a shared message queue that makes messages available to each other TOS gateway in the blockchain network. Some embodiments may further comprise recovering the symmetric key by requesting one of the key shares from the second gateway in the blockchain network, and reconstructing the symmetric key using the one of the key shares.

Abstract: A node on a blockchain network may receive an operation to initiate a token swap between a first party with a first token on a first blockchain network and a second party with a second token on a second blockchain network, receive a refund request operation, and receive a freeze operation from a committee preventing claiming of the first and the second token.