Abstract: Abstract: Under the background of cloud network convergence， the security and reliability of dedicated line scenarios are threatened. Therefore， this paper proposes a security protection method for dedicated line scenarios in cloud network based on SRv6 service chain technology. Starting from data， voice and the Internet， we should clarify the business characteristics of the cloud network dedicated line scenario， introduce SRv6 service chain technology into the cloud network structure， achieve node level by level jump， and improve the efficiency of network resource conversion； Analyze the security requirements of cloud network dedicated line scenarios， divide the security protection of cloud network dedicated line scenarios into two stages: uploading data and downloading files， calculate network traffic limit functions and constraints， create data sharing keys under the premise of shared connection protection mechanism， uniformly process data sharing seeds， and complete the security protection goals of cloud network dedicated line scenarios. The experimental results show that the proposed method can sensitively perceive abnormal attack behavior， and has fast security protection speed and strong robustness.

Key words: Key words: SRv6 service chain, special line scenario, cloud computing, safety protection, blockchain