Blockchain and smart contract for digital certificate


Because of the popularity of the Internet, the integration services have gradually changed people daily life, such as e-commerce activities on transactions, transportation and so on. The E-auction, one of the popular e-commerce activities, allows bidders to directly bid the products over the Internet. As for sealed bid, the extra transaction cost is required for the intermediaries because the third-party is the important role between the buyers and the sellers help to trade both during the auction. In addition, it never guarantees whether the third-party is trust. To resolve the problems, the blockchain technology with low transaction cost is used to develop the smart contract of public bid and sealed bid. The smart contract, proposed in 1990 and implements via Ethereum platform, can ensure the bill secure, private, non-reputability and inalterability owing to all the transactions are recorded in the same but decentralized ledgers. The smart contract is composed of the address of Auctioneer, the start auction time, deadline, the address of current winner, the current highest price. In the experiments, the accounts are created through Ethereum wallet. In miner stage, the MinerGate is used in miner stage for obtaining money to pay the transaction fee. At recorder stage, the nodes of blockchain are synchronized to generate smart contract.



Peer-to-peer computing , Cryptography

Software And Hardware

• Hardware: Processor: i3 ,i5 or more RAM: 4GB or more Hard disk: 16 GB or more • Software: Operating System : Windows2000/XP/7/8/10 Apache Tomcat server Frontend :-Java(Jsp/Servlet) Backend:- MYSQL Eclipse,geth