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.