A HYBRID BLOCKCHAIN-BASED KEY MANAGEMENT FRAMEWORK FOR ENHANCING SECURITY, TRUST, AND PERFORMANCE IN DIGITAL COMMUNICATION SYSTEMS

Abstract

Secure key management is fundamental to the confidentiality, authentication, and integrity of digital communication, yet centralized key servers and single-chain blockchain designs present competing limitations in trust, privacy, auditability, and performance. This paper develops a hybrid blockchain-based key management framework that assigns frequent and sensitive lifecycle operations to a permissioned private blockchain while anchoring non-sensitive proofs to a public blockchain. A qualitative conceptual methodology was used, combining a concept-centric literature review, comparative analysis, framework design, and evaluation of an educational website prototype. The proposed architecture integrates users and devices, private-chain validators, smart-contract policy enforcement, public proof anchoring, and security monitoring. Smart contracts automate registration checks, key requests, authorization, rotation, revocation, and audit events without storing secret key material on-chain. The conceptual comparison indicates that the hybrid approach offers a more balanced security profile than centralized, public-only, or private-only alternatives: confidential operations remain controlled and responsive, while externally verifiable hashes strengthen integrity and accountability. The prototype demonstrates the framework and key lifecycle through an accessible web interface, but it is not a live blockchain implementation. The study concludes that hybrid blockchain can improve trust and operational efficiency only when accompanied by robust key custody, contract assurance, privacy-preserving metadata design, governance, and recovery mechanisms. Future work should deploy a working prototype, benchmark latency and throughput, test adversarial scenarios, and assess usability in realistic communication environments.