In order for validators to verify purchase history, purchase data generated by kiosk is recorded on the blockchain and is made public. [Figure] shows kiosk server storing confirmed purchase transactions in the contract on the blockchain and in IPFS, a decentralized file system. The contract stores lists of data, while IPFS stores the actual data that can be accessed via links recorded in the contract’s lists.
It contains sources from smart contracts to store the blocks' heads.
It contains the necessary libraries to create blocks with purchase transactions.
It contains codes that collect purchase transactions, create blocks, and store them in smart contracts and IPFS.