A Blockchain-Based Access Control with Micropayment Channels

A blockchain-based access control system result from the idea that only a user with access rights (i.e., possession of the corresponding private key) can use the transaction's value on the blockchain. In the Bitcoin payment system, all the activities of users are stored on the public blockchain. However, with the increase of users and the number of transactions, the traditional blockchain based system cannot provide fast processing due to the limited throughput of the blockchain. To solve these problems, an off-chain transaction has been proposed. The most famous method of building the off-chain transaction is a micropayment channel in the Bitcoin payment system. Users create a payment channel among them and all most transactions that occur in the payment channel are stored on the off-chain, except for some transactions. In this paper, we propose an enhanced blockchain-based access control system for reducing the cost of transactions. A grantor and a grantee create the micropayment channel between them. All the activities of them are stored as the off-chain transaction and when they want to close the channel, the last committed off-chain transaction is broadcasted to the blockchain network. As a result, the cost of the transaction can be reduced by reducing the number of transactions stored in the on-chain.