Smart Tender/Contract Management System Using Blockchain

A tender management system built on Hyperledger blockchain. Tender documents, bids, company profiles and approval or rejection decisions are recorded securely, making the process transparent.

Users connect a wallet such as MetaMask to the web front end. Each record (for example a product batch, certificate or vote) is written by a Solidity smart contract on an Ethereum test network. The contract checks who is allowed to add or update data, so only authorised accounts can write. Anyone with the record ID can verify its full history, which cannot be edited afterwards.

Records on a blockchain are shared across nodes, linked by cryptographic hashes and cannot be altered without consensus. This gives tamper-proof history and removes the need to trust one central administrator.

A program stored on the blockchain that runs automatically when its conditions are met. In Ethereum it is written in Solidity, compiled to bytecode and executed by every node, so its result cannot be changed by one party.

It follows a three-tier architecture: the browser shows the user interface, the server-side code handles logic and validation, and the MySQL database stores records. Requests travel over HTTP and responses are rendered as HTML or JSON.

All queries use prepared statements with bound parameters, so user input is never joined into the SQL text. Inputs are also validated on the server.

We followed an iterative (incremental) model: requirements and a basic design first, then modules built and tested one by one, with the guide's feedback after each review. It suits a project where requirements become clearer as we build.

Unit testing of each module, integration testing of the complete flow and system testing with real inputs. Test cases with expected and actual results are listed in the report, including invalid inputs.

The current version is tested on a limited dataset or number of users. Future work includes deploying on the cloud, adding more features or languages, improving accuracy with more data and building a mobile version.