Block chain technology based dues payment system

Blockchain technology is a decentralized technology that records data in a secure, unalterable and indelible distributed ledger, which has become widespread today and will be even more prominent in the future. Saving data in the blockchain network is safer than saving it in the database. This study is about ensuring that the dues payments of apartment residents in a site are made in a blockchain-based system. In the study, first of all, metamask wallets were defined for all apartment residents. Ethereum-based smart contracts have been written in the background of the system for each apartment resident to make their payments on the blockchain basis and with metamask wallets. The interface smart contract connection is made using the Truffle development framework. Site manager, apartment and flat information are defined in smart contracts. In addition, the developed interface is designed to have separate user and administrator logins. It has been ensured that the administrator can update the tenants, landlord, amount of dues and other information in the system. The interface has been designed to list in detail the subscription payments made by the apartment residents on the administrator's side. On the user login page, the amount paid, the account to which it was sent, the apartment name of the sender, the apartment number and the date it was sent are kept. Dues payments made by the residents of the apartments are kept in the permanent memory area of the smart contract in the blockchain network thanks to data mappings and this information is reported when requested. Separate functions are defined in the smart contract for each transaction to be made. Information about monthly payments is recorded as a warning in the relevant block of the blockchain network via events and can be viewed publicly from the network if desired. If a report of the payments is requested, the data saved in the permanent memory is used through the functions in the smart contract for filtering. The study provides traceability and transparency in terms of data security and dues tracking in apartment dues management. The study was done with Solidity software language. Virtual wallets were used in the testing phase. Since the transaction fee charged during the dues payment is high, the code lines have been minimized during the software phase to minimize the Ethereum Gas fee. Since the code lines in the software have been reduced, the fee cut during coin transfer has been reduced to a minimum.