A decentralized public key management system for named data networks based on blockchain, which solves the Compromised Certificate Authority (CA) Problem. The system divides the power of an individual CA among multiple Public Key Miners (PKMiners) that maintain the public key blockchains. The majority rule in name-principal validation allows the present invention to tolerate compromised PKMiners without causing any damage.

In some examples, in response to a request from a client device for information relating to a transaction stored by a blockchain, a system identifies, using information stored in a distributed storage system that stores data for the blockchain, multiple data owner entities from which permissions are to be obtained for access of the information, and determines an authorization requirement for the information based on a smart contract. The system sends authorization information based on the authorization requirement to trigger a retrieval of authorization tokens from the identified data owner entities for access of the information, and sends the information to the client device in response to receiving the authorization tokens.

A diamond asset comprising one or more diamonds and an encryption chip is used to asset-back a cryptographic token that can be used to conduct transactions. The cryptographic token is written to a blockchain using a smart contract that is configured to enable a transaction associated with the token in response to two or more of: a signature by the encryption chip, a signature by the owner of the diamond asset, and a validation of a visual layout of the diamond asset.

A user authentication method performed by an authentication management server constituting a block chain network with a target device may comprise receiving, from the target device, a transaction including authentication information of a user and a unique value of the target device; determining a token of the user stored in a smart contract based on the authentication information; and authenticating the user based on validity information of the token, ownership information of the token, and the transaction.

Secure management of keys and identities of an object manufactured by a manufacturer having a manufacturer key pair, and a client having a client key pair, the management being carried out using a decentralized blockchain database. The method includes generation of a manufacturing key pair; and publication and recording, in the blockchain, of the decentralized object identifier used to obtain the public key of the object. When a client purchases the object from the manufacturer, the method includes providing, by the object manufacturer, the object identifier, and the public manufacturing key to the client; and updating the blockchain. When the object is switched on for the first time, the object enrolls itself by generation of a utilization key pair; auto-enrollment using the manufacturing key pair; and replacement, in the blockchain, of the public manufacturing key associated with the object identifier with the public utilization key associated with the object identifier.

Methods and systems are provided for crowdsourced funding via a blockchain system. A token contract, associated with a token issuer, is generated on a blockchain system. Tokens are issued to a plurality of token holders. Each of the plurality of token holders is allowed access to a feedback mechanism associated with the token issuer. A performance of the token issuer in an associated field is monitored to provide at least one performance metric. A dividend is paid to each token holder proportional to a number of tokens held by the token holder after a predetermined amount of time based on the at least one performance metric.

Systems and methods are disclosed with respect to using a blockchain for managing the subrogation claim process related to a vehicle accident, in particular, determining fault as part of the subrogation process. An exemplary embodiment may include receiving an electronic notification of a vehicle collision; receiving sensor data (such as telematics, image, audio, vehicle operational, or other sensor data) related to the vehicle collision; determining a percentage of fault of the vehicle collision for one or more vehicles, vehicle systems, and/or drivers based upon, at least in part, analysis of the sensor data collected; and creating a blockchain for the vehicle collision with one or more links to the sensor image data and an indication of the percentage of fault(s) determined to facilitate blockchain-based claim handling.

A system, method, apparatus, and computer program product for interactively broadcasting value via a sound, a Wi-Fi, a Bluetooth, an email, a messaging, an RFID, or an NFC to incentivize direct consumer engagement. The system produces verifiable data on customer preferences, habits, and purchasing while using secure digital cryptographic technology to convey an item of value. The system is configured to transact a digital token normally carried on a blockchain leger in an off-ledger condition. The digital token is embedded with a media content. A mobile computing device having a representation of a digital wallet is configured to detect the digital token, decode the digital token and is transfer the digital token back to the blockchain ledger. When validated by the blockchain ledger, the digital token is transacted to a digital wallet on the blockchain ledger.

A global resource locator (GRL) device can be used to track a physical asset. The GRL device can a semiconductor chip with a processor and a timing device. The semiconductor chip can generate a timing signal. The GRL device can include a blockchain, a communication device, and a memory in logical communication with the processor. The memory can store an identifier, a public key, a private key, and a hash. The communication device can communicate wirelessly with an authenticated radio source, the micro sized timing device, and the blockchain. Each authenticated radio source can be located at a respective reference location. The communication device can receive wireless timing signals from at least three authenticated radio sources. The GRL device can be affixed to a product.

A method and system for determining whether a consensus has been achieved for adding a block to a distributed ledger. The system receives a candidate block to add to the distributed ledger and receives block approvals of approving participants for the candidate block. The system calculates a total block approval stake that the approving participants have in the distributed ledger. The system identifies a total stake that participants have in the distributed ledger. When the total block approval stake is at least a threshold fraction of the total skate, the system indicates that the consensus has been achieved for adding the candidate block to the distributed ledger.