Research On Data Service Middleware Based On Cloud-edge Collaboration

With the development of informatization,although the construction of smart parks has improved management efficiency,and the establishment of building energy consumption monitoring platforms has reduced building energy consumption,but the established access control,security,elevator,building management and control platforms and other systems are not connected to each other,resulting in many subsystems forming information islands,and the information is not unified and cannot be interconnected,which made the management of building energy consumption in different regions more complicated.To solve the above problems,this thesis proposed a new middleware architecture for cloud-edge collaboration.The data service middleware is composed of a cloud data service platform and edge-end components,including a new set of edge-end data connection methods and cloud-edge synchronization rules.In this way,the middleware that cooperates with the cloud and the edge provided a general solution for data acquisition and transmission of intelligent buildings and interconnection of subsystems in the park.The main research and work contents of this thesis are as follows:(1)A cloud-edge collaboration architecture is proposed to solve the problem of difficult programming and heavy workload for uploading data from multiple running heterogeneous subsystems.The middleware based on cloud-edge collaboration is designed and implemented in detail.Among them,the cloud platform is mainly responsible for the management of user rights,visual configuration and communication monitoring,and the edge components are mainly responsible for the dynamic configuration and access of building data,encrypted transmission of building data based on TCP/IP protocol,dynamic configuration storage of building data and subsystems data synchronization.(2)A new set of edge-end data compatible connection method is proposed.Aiming at the problem of various sources of building data acquisition subsystems at the edge,this thesis provided a solution that is compatible with three common sources according to different building conditions for the first time,that is,the subsystem with OPC(OLE for Process Control)directly uses the JEasy OPC access method;the subsystem with API(Application Programming Interface)adopts the distributed database access method;other subsystems use crawler mode.This thesis abstracted this compatibility method into a component and integrated it into the middleware.Users can access building data through dynamic configuration;at the same time,the middleware also considered the data characteristics to provide building data timing storage component based on different scenarios and building data encryption transmission component,adopting a variety of strategies to ensure the stable acquisition and transmission of data.(3)A set of characteristic synchronization rules for summarizing the data of different subsystems of the edge end to the cloud is proposed.The data synchronization idea of cloud-edge collaboration based on the virtual file system is designed and implemented.Users can log in to the cloud platform at any time and place to perform data synchronization configuration,and the middleware will save the configuration file to the cloud server.The user can download the configuration file on any edge ends,and log in to the edge-end middleware to start a configuration file.This method solved the connection problem of subsystems.In the actual scenario,the middleware mentioned in this thesis has been applied to the smart building and smart park projects and has been tested for a long time,which made up for the difficulty and heavy workload of writing programs one by one for subsystem access and better provided users with data services.