Autonomous zero-trust security assurance for multi-domain network slicing: a systematic review of 5G-advanced and 6G research

Network slicing represents an important architectural principle in 5G-Advanced, Beyond-5G, and early 6G systems, allowing the existence of several logically separate networks with diverse needs running over common radio, transport, core, edge, cloud, and application environments. Due to the nature of network slicing where slices might go across administrative, technical, and service boundaries, the use of perimeter-based security solutions is insufficient to ensure trust, isolation, adherence to policies, and resilience. This systematic review focuses on zero-trust architecture, trust management, and autonomous security assurance for multi-domain network slicing. Following PRISMA guidelines, searches were conducted in Scopus, IEEE Xplore, and Web of Science for articles from January 2020 to12 June 2026. Out of 320 papers identified in the search process, 25 unique papers were selected for qualitative analysis. The literature review is divided into six themes: authentication and authorization; blockchain and decentralized trust; zero-touch and autonomous assurance; AI/ML-based security; programmable isolation and enforcement; and network digital twin, privacy, and 6G governance. The literature clearly shows that while there have been considerable advancements made in the individual security technologies, they are yet to be fully integrated within the end-to-end processes like verification, trust negotiation, telemetry, assessment, enforcement, remediation, and post-action verification.