Post-Quantum Cryptography for Cloud Security: Architectures, Challenges, and Migration Strategies

Abstract

Quantum computing is developing rapidly and is expected to challenge the security of the cryptographic systems used in modern cloud computing. Today, most public-key encryption methods, including RSA and Elliptic Curve Cryptography (ECC), depend on mathematical problems that are difficult for classical computers to solve. However, quantum computers could solve these problems much faster using Shor’s algorithm, making current encryption techniques vulnerable in the future.
Cloud computing now supports many essential services, including banking, healthcare, e-commerce, and government systems. Because of this, protecting sensitive data for the long term has become increasingly important. One major concern is the “harvest now, decrypt later” approach, where attackers collect encrypted information today with the goal of decrypting it once powerful quantum computers become available. This has increased the need for Post-Quantum Cryptography (PQC), which is designed to resist attacks from both classical and quantum computers.
This research paper examines how post-quantum cryptography can improve cloud security. It discusses PQC algorithms being standardized by the National Institute of Standards and Technology and focuses on key approaches such as lattice-based, hash-based, and code-based cryptography. The paper also analyses their strengths, limitations, and suitability for cloud environments.
In addition, the paper proposes a hybrid migration framework that combines traditional cryptographic methods with post-quantum algorithms. This approach supports gradual adoption, backward compatibility, and cryptographic flexibility while minimizing disruption to existing cloud systems.