Abstract: The network operating system (NOS) is the key to breaking through the "manageable and uncontrollable" limitations of large-scale wide area networks. The future NOS is the “brain” of network that provides intelligent, secure, flexible, and customizable network capabilities, and it promotes the Internet's evolution from consumption to production kind. To achieve the "manageable and controllable" network, the current research related to NOS is analyzed, and the concept and architecture of NOS are put forward systematically. The research progress, target architecture and development trend of NOS are studied from the "data plane-control plane-service plane". Finally, the potential application scenarios are summarized.

Key words: future network, network operating system, cloud network convergence, service customization