Lightweight Quantum-Resistant Group Key Management for Large-Scale IoT Networks Using Lattice Cryptography

Abstract

Secure multi-recipient Internet of Things communication in resource-constrained environments requires cryptographic protocols that are light computational requirements, scalable in bandwidth for large group sizes, and quantum-resistant. Existing group and dual-receiver encryption schemes achieve efficiency using elliptic curve cryptography but lack post-quantum security, which could be compromised by polynomial-time computations on powerful quantum computers. In contrast, current lattice-based alternatives incur prohibitive signature overhead and are unsuitable for embedded deployment. Hence, the research introduces LAGDR (Lattice-Authenticated Group Keying with Dynamic Rekeying), a protocol combining ML-KEM-512 key encapsulation for quantum-resistant key agreement, TinyJAMBU authenticated encryption for lightweight bulk data protection, and Falcon-512 signatures-the first consistent 128-bit post-quantum framework integrating ultra-lightweight AEAD with a fast-verifying compact lattice-based signature scheme for scalable multi-party IoT communication scenarios. Unlike Conventional per-recipient encryption paradigms, LAGDR employs a binary tree key hierarchy, achieving O(log n) rekeying complexity and reducing 512-member group operations from 512 encryptions to 9 while maintaining 666-byte signatures and 800-byte public keys. TinyJAMBU's hardware-optimized permutation (150 cycles/byte)for bulk encryption and Falcon's NTRU structure for sub-5ms signature verification on ARM Cortex-M4 microcontrollers. ML-KEM 512's reduced key sizes enhance bandwidth efficiency without compromising quantum security for target IoT applications.