The industrial Internet has promoted the intelligent development of the entire manufacturing service system by closely connecting and integrating equipments,production lines,factories,suppliers,products and customers through an Internet platform.China attaches great importance to the development of industrial Internet,and puts forward the latest development goals in the field of industrial Internet technology.The intra-enterprise industrial Internet is an important part of industrial Internet,interconnecting industrial equipments,information systems,business processes,enterprise products and services,and personnel,and realizing efficient connections from the shop floor level to the decision-making level.Firstly,it introduces the current status of the development of intra-enterprise industrial Internet from the perspectives of intra-enterprise industrial Internet standards,intra-enterprise industrial Internet devices and intra-enterprise industrial Internet applications.Secondly,the problems in the development of intra-enterprise industrial Internet are analyzed in depth from seven aspects,that is,architecture,network identification,opera-ting system,real-time,reliability,compatibility and security.Then,the proposed measures for the development of intra-enterprise industrial Internet are presented,and the collaborative innovation mechanism and policies of intra-enterprise industrial Internet are discussed.Finally,the future development of intra-enterprise industrial Internet is summarized.

In the application of traditional cryptography,people always assume that the endpoints are secure and the adversary is on the communication channel.However,the prevalence of malware and system vulnerabilities makes endpoint compromise a se-rious and immediate threat.For example,it is vulnerable to various attacks such as memory content being destroyed by viruses,randomness generator being corrupted,etc.What's worse,protocol sessions usually have a long lifetime,so they need to store session-related secret information for a long time.In this situation,it becomes essential to design high-strength security protocols even in the setting where the memory contents and intermediate values of computation (including the randomness) can be exposed.Ratchet key exchange is a basic tool to solve this problem.In this paper,we overview the definition,model and construction of ratchet key exchange,including unidirectional ratcheted key exchange,sesquidirectional ratcheted key exchange and bidirectionalratcheted key exchange,and prospect the future development of ratchet key exchange.