Abstract: New 5G technologies bring large bandwidth, ultra-low latency, and high-precision synchronization opportunities for transmission bearer network. At the same time, its virtualization, flexibility, and hierarchical features bring new security challenges. This article describes security risks faced by the transmission bearer network between 5G RAN, 5G Core, MEC, and the Internet. It also analyzes typical security requirements and security protection solutions for the access of 5G RAN, 5G Core, MEC, Internet, and NMS management plane to the 5G transport network. By summarizing new security risks, new requirements, and new protection technologies faced by transmission networks in new 5G scenarios, we hope to provide reference for security requirements and protection technologies during the promotion and construction of 5G telecom networks.

Key words: 5G, transmission, slicing, security, isolation

摘要：  5G新技术为传输承载网络带来大带宽、超低时延和高精度同步机遇的同时，也因为虚拟化、灵活化和层次化等特点带来新的安全挑战．本文主要介绍5G基站、5G Core、边缘MEC及Internet之间的传输承载网络面临的安全风险，并针对基站、5G Core和边缘云、Internet和网管管理面接入5G传输网分析了典型的安全需求和安全保护方案技术．希望通过总结传输网络在5G新场景下面临的安全上的新风险、新需求和新的防护技术，为5G电信网络在推广建设过程中，提供安全需求及防护技术参考．

关键词: 5G, 传输, 切片, 安全, 隔离