Advertisement targeting with a secure identity is described. A request pertaining to supplemental content targeted to an attribute of a user is posted from a requesting system to a blockchain. It is then determined that a user profile includes an attribute that matches with the attribute of the request via the blockchain. The supplemental content is then caused to be displayed in response to the determination that the user profile includes the attribute that matches with the attribute of the request and via a user interface of a device associated with a user associated with the user profile.

A system for authenticating user identities and exchange data via a blockchain is described. Initially, first data related to a commitment being made by a user is obtained by a client device. The first data is partly based on information identificatory or a characteristic of the user. The first data is sent by the client device to a verification system. The verification system then verifies that the first data corresponds with second data generated using identification documentation of the user. The data representing the commitment to a blockchain is posted by the verification system responsive to a successful verification.

Systems and methods of decentralized block chain voting are provided. Polling data that includes a plurality of polling options and an option identifier associated with each polling option is retrieved. A customized cryptographic currency address is generated for each of the plurality of polling options based on the corresponding option identifier associated with each polling option. A specified amount of cryptographic tokens are transferred to the customized cryptographic currency address for a selected polling option. The transfer is broadcast to a cryptographic currency network for confirmation and inclusion within a block chain ledger of the cryptographic currency network.

Systems and methods for displaying a post in a social media platform are provided. The method includes storing a first hash value of original content on a blockchain, the original content stored on a server and associated with an author. The method also includes authenticating the post for authenticity using the blockchain, wherein the authenticating comprises determining whether the first hash value matches the second value. The method also includes causing the post to be displayed through the social media platform.

Disclosed is a smart contract and an automatic bargaining method for secure multi-party computation and a device embodies same. A first public key and a first private key are generated based on a homomorphic encryption algorithm in the smart contract, the first public key is sent to a demander and a supplier so that the demander and the supplier encrypt the purchase price and the sale price through the first public key, respectively; after receiving a second public key and an encrypted purchase price sent by the demander and a third public key and an encrypted sale price sent by the supplier, the encrypted sale price and the encrypted purchase price that meet the preset transaction conditions are decrypted.

Method and systems for maintaining a loyalty scheme or a royalty scheme are described. A method includes receiving a request pertaining to at least one of the loyalty scheme or the royalty scheme and targeted to an attribute of a user. It is then determined that a user profile includes the attribute of the request via a blockchain. In response to determining that the user profile includes the attribute of the request, the request for a product or a service is transmitted to a device associated with the user profile. A response to the request for the product or service is received from the device associated with the user profile. A commitment to the blockchain is then posted based on the response.

In an electronic bidding system and method, it is unnecessary to disclose to bidders a list of public keys matched to bid prices, and in which price secrecy may be proved. In a function of encryption of a bidding device 300, a public key is generated using a bid price and an IBE public key, based on an ID-Based Encryption (IBE) system having a bid value as an ID. IBE public key is obtained on combining a plurality of partial public keys matched to partial secret keys generated by a plural number of partial bid opening devices based on a combination condition enabling group decryption. A preset message for bidding is then encrypted. In a function of decryption of a bid opening device 400, a number of partial bid opening devices, which is in keeping with a satisfying number of the group decryption, perform calculations for decryption for winning bid value candidates, beginning from such candidate, the allowable bid value closest to the bid closing condition. Decrypted data obtained on combining the resulting output partial bid opening data are collated to the message for bidding to decide on winning bid value.

Systems and techniques are provided for a resource stabilization in a distributed network. A computing device in a distributed network may check the median value of a transactional resource in relation to a specified external resource. The computing device in the distributed network may compare the median value of the transactional resource to a threshold value for the transactional resource to determine whether the median value of the transactional resource is above the threshold value or below the threshold value. The supply of the transactional resource in the distributed network may be increased in response to determining that the transactional resource is above the threshold value or may be in response to determining that the transactional resource is below the threshold value.

A method for conducting an open-ended Dutch auction by facilitating a bi-directional exchange of digital assets between users on user device, wherein the method of open-ended Dutch auction comprising the steps of initiating an incoming request to start auction on a digital asset wallet, communicating the incoming request to a smart contract, determining whether the incoming request allowance is a zero value or a non-zero value to authorize the incoming request and terminating by calculating an actual price of the digital asset.

A system for authenticating user identities and exchange data via a blockchain is described. Initially, first data related to a commitment being made by a user is obtained by a client device. The first data is partly based on information identificatory or a characteristic of the user. The first data is sent by the client device to a verification system. The verification system then verifies that the first data corresponds with second data generated using identification documentation of the user. The data representing the commitment to a blockchain is posted by the verification system responsive to a successful verification.