Blockchain - Bringing Accountability in the Public Distribution System

The Central and State governments of India uses the Public Distribution System(PDS) to distribute food grains to the citizen of India at subsidized rates to ensure food security. The system is prone to losses of food grains because of prevalent corruption among the officials serving the system and also due to physical losses during storage and transport. Blockchains have become a commonly used audit trail verification utility because of its inherent nature, that it is a distributed ledger for recording transactions. This makes it a key candidate to replace the current centralized system that exists for the tracking of commodities being distributed by the PDS. Like any centralized system the current centralized system can be sabotaged by the people in administration, as it relies heavily on trust on the central authority. In this paper we propose an intelligent scheme for tracking the commodities in PDS using IoT based sensors that monitor the arrival and dispatch of commodities and generate corresponding transactions. These transactions should be stored permanently to keep track of the commodities for which a decentralized Blockchain based system is used that continuously logs every valid transaction. As the amount of transactions increase so does the data to be stored on the blockchain, hence we propose a hierarchical blockchain approach where in transaction summaries of a local blockchain are recorded as transactions in a higher level blockchain after which the local blockchains can start afresh recording newer transactions only. This approach results in reduction in the amount of data to be stored on the blockchain. At the same time one can find aggregate information at a higher level which can be used to determine the supply demand ratio. Anyone can verify the current availability of the food grains throughout the distribution network of the PDS and track the commodities right from the network of warehouses to the end point sales-the fair price shops where the food grains are delivered to the consumers. These transactions can be audited at any time as all transactions are recorded in the Blockchain which can prevent any misuse or corruption.