网络作为工业互联网三大功能体系之一，为工业全要素的全面互联提供基础设施。现有的“两层三级”工业网络难以满足工业互联网新业务、新模式的发展需求，不断出现的新型网络技术推动网络架构演进。工厂内网络向着融合、开放、灵活的方向发展，工厂外网络的服务呈现普遍化、精细化、灵活化趋势。本文给出了工业互联网网络连接框架，并建议工业企业根据业务、实时性、传输方式等需求建设工厂内网络，根据不同业务发展的要求选择三种专线和一种上网连接方式构建工厂外网络。

As one of the three main function aspects of the industrial Internet, networks provide infrastructure for the all-round interconnection of industrial elements. The existing "two-layer and three-level" industrial network is difficult to meet the development needs of the new models and services of the industrial Internet. The emerging network technologies can promote the evolution of the network architecture. The intra-factory network is developing in directions of integration, openness, and flexibility. The services of the extra-factory network are universal, refined, and flexible. At the end, the paper describes the networking framework of the industrial Internet, and suggests that industrial enterprises build intra-factory networks according to requirements for business, real-time performance, transmission methods, etc., and build extra-factory external networks by selecting three dedicated lines and one networking mode according to development requirements of different services.