Design And Application Of Embedded Operating System In Distributed System

With the continuous development of Internet of Things devices,the current society increasingly needs to have high-performance structures and high-speed and effective computing functions in embedded terminal nodes such as smart homes,smart medical,and smart transportation,so that users can meet various information Technology services.However,in the current society,most embedded systems work alone,there is little interaction between the system and the system,and few can use mutual cooperation to complete some complex calculations at the terminal nodes.In the application of distributed systems,the terminal nodes of the Internet of Things can theoretically achieve certain calculations through collaborative work.With the promotion of distributed systems,the interaction between multiple embedded systems will become a hot topic in the research of cross-integration of distributed technology and embedded technology.However,there are relatively few design researches on the market at present,and there are many problems: First,the resources in embedded devices are limited and the device specificity is strong,which makes the performance for complex calculations not high;second,The research population is small,and the research does not have an in-depth discussion on this aspect;third,there is almost no application research,and the research basically only stops at the system testing stage.Therefore,we combine embedded systems and distributed systems,and build a distributed system through multiple small embedded systems,called "Multi-embedded systems";and then on this multi-embedded system that can be used for distributed computing,the embedded operating system is designed and applied,which is a "distributed operating system" that combines distributed system and embedded operating system.In the constructed multi-embedded system,each node is composed of an STM32 board and a distributed operating system(modified and expanded by the embedded real-time operating system RT-Thread).In the whole system,a single embedded system is divided into two types: control node and computing node,and the functions of the two are different.The control node is responsible for collecting node information,managing processes and distributing computing tasks,and assigning tasks to computing nodes for execution;computing nodes implement task execution functions,and sending data of their own node information and task results to the control node or other computing nodes.The control node and the computing node work together to form the entire distributed system,and achieve the goal of completing part of the complex computing work in coordination at the terminal node.When building the entire system,we designed the distributed operating system and distributed communication mechanism.Specifically: 1)When designing a distributed operating system,it is mainly to complete the discussion and design of process management and scheduling,collaborative processing and task allocation.In the design process,it is mainly to study the mature research in the distributed system,and even the algorithms that have been applied.Code is provided in the distributed operating system in the system.2)When designing the communication mechanism,first realize the way of message transmission.Due to the operating characteristics of the system,a semi-synchronous and semi-asynchronous Client/Server communication model is adopted.Then,the remote procedure call(RPC)function is also designed and implemented to realize the control node to call a certain calculation Node.Finally,a confidentiality mechanism for information transmission is designed.Due to the characteristics of the system's miniaturization and distribution,the communication encryption scheme based on attribute encryption is adopted and designed,and it is applied to the system.On the whole,the basic functions of the system have been realized.According to actual projects,the completed distributed operating system is also applied to multiple embedded systems in actual production.Through the application implementation,it can be seen in the DALI system that the distributed operating system formed by the combination of the embedded operating system and the distributed system can be well applied in smart homes,which improves the original system with better performance.And it has achieved good results after installation and use on the product site.