The book begins with the development of IP technologies by focusing on the problems encountered during MPLS and IPv6 network development, giving readers insights into the problems tackled by SRv6 and the value of SRv6. It then goes on to explain SRv6 fundamentals, including SRv6 packet header design, the packet forwarding process, protocol extensions such as Interior Gateway Protocol (IGP), Border Gateway Protocol (BGP), and Path Computation Element Protocol (PCEP) extensions, and how SRv6 supports existing traffic engineering (TE), virtual private networks (VPN), and reliability requirements. Next, SRv6 network deployment is introduced, covering the evolution paths from existing networks to SRv6 networks, SRv6 network deployment processes, involved O&M technologies, and emerging 5G and cloud services supported by SRv6. Bit Index Explicit Replication IPv6 encapsulation (BIERv6), an SRv6 multicast technology, is then introduced as an important supplement to SRv6 unicast technology. The book concludes with a summary of the current status of the SRv6 industry and provides an outlook for new SRv6-based technologies. SRv6 Network Programming: Ushering in a New Era of IP Networks collects the research results of Huawei SRv6 experts and reflects the latest development direction of SRv6. With rich, clear, practical, and easy-to-understand content, the volume is intended for network planning engineers, technical support engineers and network administrators who need a grasp of the most cutting-edge IP network technology. It is also intended for communications network researchers in scientific research institutions and universities. Authors: Zhenbin Li is the Chief Protocol Expert of Huawei and member of the IETF IAB, responsible for IP protocol research and standards promotion at Huawei. Zhibo Hu is a Senior Huawei Expert in SR and IGP, responsible for SR and IGP planning and innovation. Cheng Li is a Huawei Senior Pre-research Engineer and IP standards representative, responsible for Huawei's SRv6 research and standardization.