Abstract: An example operation may include one or more of receiving a request associated with a key-value pair stored in a database, determining whether a state of the key-value pair has changed since a most recently received request, and in response to a determination that the state of the key-value pair has changed, generating a data block that includes a changed state of the key-value pair and adding the generated data block to a hash-linked chain of data blocks.

Abstract: One example embodiment may provide a system for trace-based transaction validation and commitment in a network. The system includes at least one endorser peer and at least one committer peer. The at least one endorser peer is configured to generate a binary trace during simulation of a transaction, resulting in an endorsed trace. The at least one committer peer is configured to validate the transaction by executing a smart contract and using the endorsed trace as a witness.

Abstract: An example operation may include one or more of registering data values, by a plurality of IoT devices, each IoT device associated with one of at least two different cloud storages, the registration of the data values having a relative order, and only one measurement being made for each IoT device per measurement at a given point in time, and proving a common ordering of at least some of the data values registered by the plurality of IoT devices, by a client application of a client device.

Abstract: An example operation may include one or more of calculating a timestamp for each transaction within a blockchain. The calculating of the time stamp includes setting an incremental number to each key and value modified in the transaction, and incrementing the incremental number when the transaction within the blockchain is processed. The example operation may also include determining a relative order of change made to a smart-contract state.

Abstract: An example operation may include one or more of obtaining a machine-readable code from a first document among a set of documents, extracting a probabilistic data structure from the machine-readable code which includes probabilistic hashes accumulated from the set of documents, determining whether a document hash of a second document is included within the probabilistic data structure, and in response to a determination that the document hash is included within the probabilistic data structure, outputting a notification indicating the second document is included in the set of documents.

Abstract: An example operation may include one or more of storing a data block that is included within a sequential chain of data blocks and which comprises a probabilistic data structure stored therein, receiving a request to verify another data block, determining whether a probabilistic hash of the other data block is included within the probabilistic data structure of the stored data block, and in response to a determination that the hash of the other data block is included within the probabilistic data structure, storing an indicator that the other data block is included within the sequential chain of data blocks.

Abstract: A method, system and apparatus of for validating uniqueness of a non-disclosed element of data, including in response to receiving a plurality of elements, generating an index of the plurality of elements of data received from a data store to create uniquely indexed data, generating filters from the index, generating a hash tree for the uniquely indexed data using the index, and validating a unique element of data from the hash tree and filters.

Abstract: An example operation may include one or more of executing, by an endorser node, a smart contract to generate a blockchain transaction data, generating, by the endorser node, metadata specific to the endorser node, concatenating, by the endorser node, the metadata with the blockchain transaction data, signing, by the endorser node, a concatenation result data with a key of the endorser node, and providing, by the endorser node, the signed concatenation result data to a committer node for verification.

Abstract: An example operation may include one or more of receiving a request to store a data block on a hash-linked chain of data blocks, dynamically selecting a subset of non-consecutive data blocks which have been previously stored within the hash-linked chain of data blocks, generating a linking hash based on a hash value of the data block to be stored and an accumulation of hash values from the subset of non-consecutive data blocks, and adding the data block to the hash-linked chain of data blocks, wherein the added data block includes the linking hash stored therein.

Abstract: An example operation may include one or more of connecting, by an attester node, to a blockchain network A configured to store hashes of blocks A, coupling, by the attester node, the blockchain network A with a blockchain network B configured to store hashes of blocks B, receiving, by the attester node, a request from the blockchain network A to send a hash of a block A produced at a time t1 (AHash_1) to the blockchain network B, confirming, by the attester node, that the blockchain network A has stored a hash of a block B produced at a time t0 (BHash_0), sending, by the attester node, the AHash_1 to the blockchain network B to be stored, receiving, by the attester node, a hash of the block B produced at the time t1 (BHash_1) from the blockchain network B, confirming, by the attester node, that the blockchain network B has stored a hash of a block A produced at the time t0 (AHash_0), and providing, by the attester node, the BHash_1 to the blockchain network A to be stored, wherein the t0 is less than the t1.

Abstract: An example operation may include one or more of receiving a request for performing a post-commit validation of a chain of blocks on a distributed ledger, the chain of blocks being encrypted using an encryption key, requesting cooperation from one or more auditor nodes associated with the distributed ledger, each auditor node comprising a partial secret of a decryption key corresponding to the encryption key, and, in response to receiving partial secrets from a minimum threshold of auditor nodes, recovering the decryption key based on the received partial secrets, decrypting the chain of blocks based on the recovered decryption key, and validating content included within the chain of blocks.

Abstract: An example operation may include one or more of generating, by a first blockchain client, a transaction to a blockchain network to transfer a document, transferring over a private channel, by a second blockchain client, a first key to the first blockchain client, the private channel providing a point-to-point connection between the first and second blockchain clients, encrypting the document using a shared key, transferring, by the first blockchain client, the encrypted document over the private channel, generating, by the second blockchain client, a transaction to acknowledge receipt of the encrypted document, and transferring the shared key encrypted with the first key.

Abstract: An example operation may include one or more of generating, by a block generator, modified blocks for source ledgers, receiving a merge request to merge a plurality of source ledgers into a merged ledger, identifying the plurality of source ledgers, generating a genesis block from modified blocks of the identified source ledgers, ordering blocks, by a committer node or peer, in the merged ledger based on the genesis block, and validating a block order in the merged ledger.

Abstract: An example operation may include one or more of connecting, by an attester node, to a source blockchain network configured to store hashes of source blocks, collaboratively coupling, by the attester node, the source blockchain network with a target blockchain network configured to store hashes of target blocks, receiving, by the attester node, a request from the source blockchain network to store the hash of the source block on the target blockchain network, confirming, by the attester node, that the source network has a previously stored hash of the target block, in response to the confirmation that the source blockchain network has a previously stored hash of the target block, allowing, by the attester node, to store the hash of the source block on the target blockchain network, and continuing, by the attester node, a collaboration between the source blockchain network and the target blockchain network.

Abstract: An example operation may include one or more of selecting, by a peer, a block from a blockchain based on a selected smart contract of a plurality of smart contracts, requesting, by the peer, transactions associated with the selected smart contract, confirming, by the peer, that received transactions associated with the selected smart contract belong to the selected block, verifying, by the peer, that all of the requested transactions associated with the selected smart contract have been received, and synchronizing, by the peer, the selected smart contract based on the received transactions.

Abstract: An example operation may include one or more of receiving, by a broadcast server node, data from a plurality of data provider nodes; and executing, by the broadcast server node, a smart contract to: encrypt the data with encryption keys; generate a broadcast queue based on the encrypted data; and assign a subset of consumer nodes authorized to receive the encrypted data of the broadcast queue.

Abstract: An example operation may include one or more of receiving, by a committer node or peer of a blockchain network, a block comprising a lock request that locks a partial state of a smart contract, the lock request comprising a submitter identifier and a lock delay, the committer node or peer configured to process blocks of transactions, the method further comprising, validating the lock request, committing transactions comprising the submitter identifier with no delay, and committing transactions not comprising the submitter identifier after the lock delay.

Abstract: An example operation may include one or more of computing historical patterns related to fraudulent attempts from a transaction log, predicting future fraud attempts from public data, correlating the historical patterns and the predicted future fraud attempts, modifying one or more endorsement policies based on the correlations, and adding the modified one or more endorsement policies to a smart contract.

Abstract: An example operation may include one or more of computing historical patterns related to fraudulent attempts from a transaction log, predicting future fraud attempts from public data, correlating the historical patterns and the predicted future fraud attempts, modifying one or more first endorsement policies based on the correlations, preventing modifying one or more second endorsement policies, the one or more second endorsement policies providing read-only access, and adding the modified one or more first endorsement policies to a smart contract.

Abstract: An example operation may include one or more of sending a transmission process from a client with an application, the application coupled to the client, receiving the transmission process from the client via a multistate peer network, the multistate peer network includes a ledger, an endorsement policy, and a smart contract, generating, from the transmission process, a multistate endorsement based ledger process, establishing a threshold state logic and a final state logic via the smart contract, the threshold state logic is set by the minimum number of endorsements required to commit to the ledger set by the endorsement policy, a commitment to the ledger triggers the final state logic, and executing post-settlement processes via the final state logic.