Blockchain-Based Single Sign-On Authentication for Secure Academic Portal Access

In modern multi-service academic environments, the proliferation of login credentials across platforms exposes users to security risks and usability challenges. This paper proposes a decentralized Single Sign-On (SSO) system utilizing Ethereum blockchain and smart contracts to streamline authentication for educational institutions. The system integrates MetaMask for user identity verification and employs JSON Web Tokens (JWT) to efficiently handle session management off-chain, enhancing scalability and response time. Role-based access controls are embedded directly within smart contract logic, eliminating reliance on centralized authorities. A functional prototype is deployed on Ethereum testnet and validated through a case study on an academic portal, demonstrating improved security, transparency, and ease of use. This approach provides a simplified, resilient, and future-ready alternative to conventional authentication frameworks.