Abstract: An example operation may include one or more of storing chaincode that comprises a plurality of statements to be executed, receiving a message to endorse a blockchain storage request, delaying execution of one or more statements within the chaincode based on content included within the chaincode, endorsing the blockchain storage request via execution of remaining statements included in the chaincode which are not delayed to generate an endorsement result, and transmitting the endorsement result to a node.

Abstract: An example operation may include one or more of identifying a new member (M1) to a permissioned database, creating a new group including the new member and one or more previously identified members (MP), modifying a world state of the permissioned database to identify a set of members in the new group with access to the permissioned database, and responsive to the new member (M1) being identified, creating a new entry (TX1) to the permissioned database using an encryption key (K1) associated with the new member (M1).

Abstract: An example operation may include one or more of storing a broadcast encryption tree comprising a set of cryptographic keys disposed in a hierarchical tree format, distributing a partial set of keys from the broadcast encryption tree to each respective peer from among a group of peers included in a blockchain network, receiving, from a user device, an identification of at least one peer included in the group of peers for processing a blockchain transaction, selecting a subset of keys from among the set of cryptographic keys in the broadcast encryption tree which enables at least one peer to decrypt transactions and doesn't enable the remaining peers included in the group of peers to decrypt transactions, and transmitting broadcast encryption information about the selected subset of keys to the user device for performing encryption of the transactions.

Abstract: An example operation may include one or more of identifying a blockchain transaction, storing the blockchain transaction in a blockchain, assigning the blockchain transaction a transaction number and a block number, hashing a portion of blockchain transaction data associated with the blockchain transaction, and updating a blockchain index based on the hashed portion of the blockchain transaction.

Abstract: A method, computer system, and a computer program product for communicating between a bicycle and a vehicle to prevent vehicle open door accidents is provided. The present invention may include collecting data from a bicycle device associated with the bicycle. The present invention may also include determining the vehicle is involved in at least one high-risk activity. The present invention may then include determining the bicycle is in a proximity of the vehicle involved in the at least one high-risk activity. The present invention may further include transmitting, by the bicycle device, a plurality of proximity alerts to the vehicle involved in the at least one high-risk activity.

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 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 generating evidence for a set of transactions, wherein the generating of the evidence comprises identifying one or more blocks containing one or more of the transactions in the set of transactions, and generating a branch of a hash tree of the set of transactions for each of the one or more blocks.

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 storing a broadcast encryption tree comprising a set of cryptographic keys disposed in a hierarchical tree format, distributing a partial set of keys from the broadcast encryption tree to each respective peer from among a group of peers included in a blockchain network, receiving, from a user device, an identification of at least one peer included in the group of peers for processing a blockchain transaction, selecting a subset of keys from among the set of cryptographic keys in the broadcast encryption tree which enables at least one peer to decrypt transactions and doesn't enable the remaining peers included in the group of peers to decrypt transactions, and transmitting broadcast encryption information about the selected subset of keys to the user device for performing encryption of the transactions.

Abstract: An example operation may include one or more of identifying a blockchain transaction, storing the blockchain transaction in a blockchain, assigning the blockchain transaction a transaction number and a block number, hashing a portion of blockchain transaction data associated with the blockchain transaction, and updating a blockchain index based on the hashed portion of the blockchain transaction.

Abstract: An example operation may include one or more of connecting, by an asset server, to a source blockchain configured to store a digital asset of an asset owner, enciphering and locking, by the asset server, the asset in the source blockchain, manifesting, by the asset server, the asset as a linked asset in a target blockchain, tracking, by the asset server, a life cycle of the asset, detecting, by the asset server, an end of the life cycle of the asset, reflecting, by the asset server, the end of the life cycle of the asset in the source blockchain, and creating, by the asset server, the asset in the target blockchain.

Abstract: An example operation may include one or more of receiving an asset from an asset owner, initiating an integrity of the asset and entering the asset into a primary chain of genesis, signing the asset and locking the asset in the primary chain of genesis, manifesting the asset as a linked asset in a derivative chain of genesis, detecting a timeout of the asset in the primary chain of genesis, ending a life cycle of the asset in the primary chain of genesis, and creating a new asset in the derivative chain of genesis based on the asset.

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 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: A method, computer system, and a computer program product for communicating between a bicycle and a vehicle to prevent vehicle open door accidents is provided. The present invention may include determining, by a bicycle device, a bicycle is in a stationary state. The present invention may then include sending, by the bicycle device, a request to a user to confirm that the bicycle is in the stationary state. The present invention may further include receiving, from the user, a response to the sent request, wherein the user confirms that the bicycle is in an active state.

Abstract: An example operation may include one or more of a method for providing a one-step transaction submission in a blockchain network, comprising sending a transaction proposal, by a client node, to one or more peers of a plurality of peers, simulating a transaction associated with the transaction proposal, by at least one peer of the plurality of peers, evaluating, by an endorser peer, whether an endorsement policy has been fulfilled, and when the endorsement policy has been fulfilled, sending the transaction to at least one orderer node to be committed to a ledger, by the endorser peer.

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: A method, computer system, and a computer program product for communicating between a bicycle and a vehicle to prevent vehicle open door accidents is provided. The present invention may include collecting data from a bicycle device associated with the bicycle. The present invention may also include determining the vehicle is involved in at least one high-risk activity. The present invention may then include determining the bicycle is in a proximity of the vehicle involved in the at least one high-risk activity. The present invention may further include transmitting, by the bicycle device, a plurality of proximity alerts to the vehicle involved in the at least one high-risk activity.

Abstract: A method, computer system, and a computer program product for communicating between a bicycle and a vehicle to prevent vehicle open door accidents is provided. The present invention may include collecting data from a vehicle device associated with the vehicle and a bicycle device associated with the bicycle, wherein the vehicle device and the bicycle device transmit and receive alert signals and proximity alerts. The present invention may also include determining the vehicle is involved in a high-risk activity. The present invention may then include determining the bicycle is in proximity of the vehicle involved in a high-risk activity. The present invention may further include transmitting, by the bicycle device, the proximity alerts to the vehicle involved in a high-risk activity. The present invention may then include transmitting, by the vehicle device, the alert signals to the bicycle device that the vehicle is involved in a high-risk activity.