FORMAL ARCHITECTURE AND PERFORMANCE VERIFICATION OF A BLOCKCHAIN-BASED DECENTRALIZED CREDENTIAL SYSTEM

Academic certificate forgery and inefficient manual verification processes continue to undermine trust in educational institutions, employers, and credential evaluation systems. Although digital verification approaches have been proposed, many remain vulnerable to tampering, lack transparency, and depend on centralized infrastructures that restrict scalability, interoperability, and resilience. This paper presents a secure and formally structured blockchain-based framework for academic credential issuance and verification, integrating decentralized storage, smart contract automation, and performance-driven system design. The proposed architecture combines Ethereum smart contracts for immutable on-chain management of certificate metadata with the InterPlanetary File System (IPFS) for decentralized off-chain storage, enabling secure, tamper-resistant, and privacy-aware credential handling. A web-based interface supports seamless certificate registration and verification, while formal algorithmic workflows govern hashing, storage, retrieval, and validation processes. To strengthen technical rigor, computational complexity analysis, gas consumption modeling, and throughput evaluation are incorporated. The prototype implementation, developed using Solidity, Python, and JavaScript, was evaluated on a controlled blockchain test-bed. Experimental results demonstrate near real-time verification with a mean latency of 2.41 seconds, stable throughput under increasing load, and low verification gas costs, confirming the efficiency of the hybrid architecture. Security analysis further demonstrates resilience against key threats, including replay attacks, unauthorized access, and data manipulation.