The 21st century marks the year of digitization due to technological improvements and has impacted the lives of the people. The growing population and demand for digitization standards, have led many governments to start investing in smart cities. The Smart city is incomplete without smart waste management in which smart bins are the intelligent waste management system. The Solid Waste Management is one of the crucial areas of research where the Smart bins are one of the perfect solutions for Asian cities with the high population density. The introduction of smart bins would make a significant impact in building smart cities with improved hygiene and environment.
“We are responsible for our waste”
Considering this motto in mind Smart dustbin is designed for public usage where the user can keep track of the waste generated by them and the processing of the waste is monitored using an android mobile application. As many countries have tax on wastage, other countries may also practice it in the future. To keep track of the waste management process and smart metering, blockchain Technology is used. Once the registration with the mobile application is completed, users will scan the QR code on the bin, which then opens it up to allow for garbage disposal. The weight sensors in the smart bin calculate the garbage weight and update the user application with weight cost, whenever the user uses it.
INTRODUCTION TO BLOCK CHAIN TECHNOLOGY
BLOCK CHAIN TECHNOLOGY STACK
The blockchain operates on a technology stack that includes the following components:
SMART CONTRACTS – Set of rules
It is the set of rules written in code for the participants in the blockchain network. By signing smart contracts, trusted transactions and agreements are carried out between nodes without any central authority or a legal system to monitor. The code controls the execution procedure. The transactions are traceable, transparent, and irreversible.
LEDGER – Record of transactions
The ledger is a file containing all information about transcations.It tracks all sets of assets from the genesis block till current value and it is stored in every node of the network. It records two important information world state and blockchain which are interconnected. The blockchain protocol builds an open, shared and trusted public ledger of transactions entity.
World state: The current values of the set of ledger states.
Blockchain: A transaction log that records all the changes that have resulted in the current world state. It records the history of changes that have resulted in the current world state.
NODES: Participants
Nodes are all devices that participate in the blockchain network. The nodes can be any kind of device like laptops, computers, or mini servers. The nodes store, preserve and forward the blockchain data, so theoretically a blockchain exists on nodes. The nodes check transaction blocks, validate, accept or reject and broadcasts the blocks to another node.
CONSENSUS RULES: Group Rule
A consensus mechanism is a fault-tolerant mechanism that is used in computers and blockchain. It enables system to achieve the necessary agreement on a single data value or a single state of the network among distributed processes or multi-agent systems. The consensus mechanism is a dynamic way of reaching an agreement in a group.
BLOCKCHAIN PROTOCOL-Communication
The communication between the nodes are achieved through blockchain protocols such as Ethereum, Corda, Ripple and Quorum in enterprice application.
BLOCKCHAIN BASED SMART TRASH BIN SYSTEM
A private blockchain network is formed between all mobile application users, smart trash bins, and municipal offices as nodes in the network. Once the QR code in the smart trash bin is scanned by the user via the mobile app, a smart contract is created. After the trash is disposed of, the data recording the credits transferred from the trash bin to the user and the cost metrics of the trash disposed of by the user is added to the smart contract. The smart contract is added to the block with other transaction details such as the time of transition, digital signatures of both user and trash bin. Every transaction that happened in a time frame is added to a particular block, which is broadcasted to all the nodes on the network and becomes part of a blockchain. Once the data is added to the blockchain, the data cannot be altered unlike other databases such as SQL. All history of transactions is secured using asymmetric cryptography. Therefore, all transactions made in the network are traceable, transparent, and irreversible.
– Dr. K. Ramalakshmi
Associate Professor
Alliance College of Engineering and Design