Built on Huawei’s pioneering research, this book provides a comprehensive introduction to the architecture, techniques, and deployment of IPv6 on-path telemetry, highlighting the most recent developments in IP network technologies. IPv6 on-path telemetry is a network Operations and Maintenance technology that has emerged alongside the development of IP network services in the 5G and cloud computing era. It has gradually achieved large-scale deployment and application. Starting with the challenges that 5G and cloud computing pose to IP networks and the shortcomings of traditional O&M, the book analyzes the differences between IPv6 on-path telemetry and traditional Operations, Administration, and Maintenance (OAM) technologies. It emphasizes the technical value of IPv6 on-path telemetry from a service perspective in the 5G and cloud era. Then, the book illustrates the technical implementation and deployment of IPv6 on-path telemetry, providing instructions supported by Huawei use cases. Finally, it explores the prospects of the IPv6 on-path telemetry industry and related techniques, drawing on Huawei’s expertise in IP networks and its research progress. This book is intended for network planning engineers, technical support engineers, and network administrators. It will also appeal to researchers, students, and professionals interested in IP network technologies and communication networks.