Encryption in Compute Networks: A Systematic Literature Review of Cryptographic Protocols, Encrypted Traffic Analysis, and Post-Quantum Migration
Abstract Encryption has become the primary mechanism by which compute networks protect the confidentiality, integrity, and authenticity of data in transit and at rest, with recent measurements indicating that roughly ninety-five percent of web traffic is now encrypted using HTTPS. This near-universal adoption has fundamentally reshaped network security practice: it protects users from eavesdropping and tampering, but it also conceals a growing share of malicious traffic, with industry telemetry reporting that a large majority of cyberattacks now traverse encrypted channels. This paper presents a systematic literature review of encryption in compute networks, organising the field into symmetric and asymmetric cryptographic foundations, transport-layer security protocols, machine-learning-based encrypted traffic analysis, encryption in resource-constrained and Internet-of-Things environments, and the ongoing migration to post-quantum cryptography following the National Institute of Standards and Technology's 2024 finalisation of the ML-KEM, ML-DSA, and SLH-DSA standards. The review examines the datasets, protocols, and evaluation criteria that recur across this literature, presents a case study of post-quantum migration in financial and cloud network infrastructure, and discusses cross-cutting challenges including key management, performance overhead, the tension between traffic visibility and user privacy, the harvest-now-decrypt-later quantum threat, and regulatory fragmentation. The paper concludes by proposing a conceptual layered hybrid-encryption architecture for compute networks that combines classical and post-quantum primitives with privacy-preserving traffic monitoring, and by outlining directions for future research. Keywords: encryption, compute networks, network security, cryptography, TLS, post-quantum cryptography, encrypted traffic analysis