A COMPARATIVE ANALYSIS OF LWE BASED POST QUANTUM CRYPTOGRAPHIC SCHEMES: BALANCING CRYPTOGRAPHIC SECURITY, EFFICIENCY METRICS, AND IMPLEMENTATION FEASIBILITY IN THE POST QUANTUM TRANSITION ERA

Abstract

The imminent threat posed by the realization of large-scale, fault-tolerant quantum computers (QCs), capable of leveraging Shor's algorithm to break foundational classical public-key cryptosystems like RSA and ECC, necessitates an immediate and comprehensive shift to Post-Quantum Cryptography (PQC). This urgency is intensified by the "Harvest Now, Decrypt Later" (HNDL) threat, which compromises long-term data confidentiality. The NIST PQC Standardization process has established Lattice-Based Cryptography as the leading family for new standards. This paper presents a comprehensive comparative analysis of major PQC schemes built upon the foundational mathematical problem, Learning with Errors (LWE). We systematically evaluate these LWE-based schemes (CRYSTALS-Kyber, CRYSTALS-Dilithium) by balancing three critical dimensions: cryptographic security (against classical and quantum attacks), efficiency metrics (key size, signature size, and operational speed), and implementation feasibility across diverse hardware environments. Our findings provide essential insights and a structured framework to guide engineers, policy-makers, and organizations in making informed decisions for the strategic and secure migration to quantum-resistant standards in the post-quantum transition era.