Lightweight Hierarchical Dynamic Index-Based Broadcast Encryption Scheme for 5G/6G Networks

Frequent group dynamics in dense 5G/6G networks impose heavy latency and security burdens on key negotiation, increasing leakage, replay, and tampering risks. This paper proposes a Lightweight Hierarchical Dynamic Index-Based Broadcast Encryption (LH-DIBE) scheme to address these issues. LH-DIBE employs time-bound dynamic indexing and a hierarchical aggregation structure to achieve efficient, scalable key updates while minimizing computational and communication costs. Furthermore, a lightweight malicious member detection mechanism is integrated to enhance security without introducing additional complexity. Formal verification and extensive simulations demonstrate that LH-DIBE ensures forward secrecy, accelerates key update cycles, and supports large-scale dynamic groups with high mobility.