This paper introduces PRISEC III, a dynamic cryptographic framework designed to balance security and performance in heterogeneous IoT environments. Unlike static, one-size-fits-all approaches, PRISEC III employs a role-based multi-level model that adapts cryptographic strategies according to data sensitivity, device constraints, and network conditions. The framework integrates lightweight symmetric primitives for efficiency, robust asymmetric methods for secure key exchange, and hybrid schemes that combine multiple layers of protection. To enhance long-term resilience, PRISEC III also incorporates post-quantum options, ensuring preparedness against emerging cryptographic threats. Evaluation results demonstrate that the approach achieves scalable security while maintaining feasible computational costs, making it suitable for large-scale and resource-constrained IoT deployments.

This research was partially the scope of projects UIDB/04466/2025 and UIDP/04466/2025. This research was also partially funded by national funds through the FCT project 16881, LISBOA2030-FEDER-00816400. whith DOI: https://doi.org/10.54499/2023.16583.ICDT

Adaptive cryptography,IoT security,Lightweight encryption,Authenticated encryption,Key management,Post-quantum cryptography

• Computer and Information Sciences - Natural Sciences
• Other Engineering and Technology Sciences - Engineering and Technology
• Electrical Engineering, Electronic Engineering, Information Engineering - Engineering and Technology