The Design And Implementation Reliable Data Transmission Mechanism In Real-time Operating System Environment

In the increasing information of today's society,computer science and network technology have been fully penetrated into all aspects of social life.With the advent of the digital information age,computer science and network technology make people's lives and work more convenient.In order to strengthen our national defense construction and realize the informatization,intelligence and integration of our army,we should make full use of computer and network technology to enhance the capabilities in a combat.In order to maximize the utilization of information,it is necessary to transmit the collected information to the switch timely,accurately,reliably and securely,and to obtain it timely for the information users.And between embedded systems,they adopt UDP multicast transmission mode to communicate effectively,so it is particularly important for the reliability of data transmission,data security.Compared with TCP and SCTP protocols ofthe data transmission network,UDP protocol has the advantage of fast speed in time,but there is the problem of poor reliability.Combined with the advantages of TCP,SCTP and UDP,the IETF proposed the draft of Reliable UDP(RUDP).The IETF enhances the traditional UDP reliability by combining the retransmission mechanism and the retransmission mechanism of the packet and congestion control.The use of data encryption algorithm technology makes data security further improved.First of all,this paper analyzes the current situation of reliable transmission mechanism in real-time embedded operating system,and studies the characteristics of current embedded system and reliable data transmission.Ithas beenfound that inthe real-time operating system real-time data transmission reliability is poor,and the system will not be paralyzed because of other defects and shortcomings,and to put forword a reliable data transmission system solution based on dual-NIC Unicast,multicast and broadcastin real-time operating system.Secondly,this paper analyzes the process communication mechanism of real-time operating system and the characteristics of inter-network communication mechanism,and proposes a method to realize dual network card switching network communication by hardware interrupt mechanism,the characteristics of the real-time operating system and the state of the process,the process of switching,the communication mechanism between processes,including synchronization,shared memory,interrupt and other communication mechanisms and network system call and network communication mechanism characteristics.Themethod is to achieve dual-network communication mechanism and the reliable transmission of data.Thirdly,this paper analyzes the characteristics of current UDP,TCP and STCP messages and proposes,put forward a method to support UDP-based Unicast,broadcast and multicast transmission.This paper summarizes the communication mechanism of UDP,TCP and STCP,including message structure of various protocols,connection establishment and closure,serial number mechanism,confirmation and retransmission mechanism and sliding window mechanism.The method realizes the reliable transmission of dual-network Unicast,multicast and broadcast transmission modes under real-time operating system.Considering the problem of data security,this paper analyzes the data encryption algorithm,which improves the security of user data.Fourthly,this paper analyzes the system requirements and completes the overall architecture design of the reliable transmission mechanism of dual-network multicast.The system has data user encryption module,dual network reliable UDP transmission module,dual network switching module,and the user system requirements were designed in detail.Fifthly,this paper realizes the dual-network reliable UDP data transmission mechanism in real-time operating system.The design and implementation of the transmitting and receiving function modules of the dual-network reliable UDP data transmission communication are completed and the function of the transmitting and receiving modules of the dual network cards is extended.In the dual-NIC function module,to achieve a dual-NIC switching,suspend work,resume work,the net-card stop work functional module design and implementation.In this paper,the functions of adding and removing UDP multicast address are designed and implemented.Sixly,the function and performance of the real-time operating system's reliable data transmission system are verified by experiments.It verifies time performance and data transmission reliability under real-time operating system Vxworks.The real-time performance of the data is verified by comparing the different size data under different network speed conditions.Through UDP datagram loss rate,the reliability of dual-network multicast UDP data transmission is verified.In this paper,the reliability of data transmission mechanism in real-time operating environment is studied in detail,and the feasibility of reliable data transmission scheme for dual-card Unicast,multicast and broadcast real-time operating system is verified.The application of the system improves the efficiency of data transmission and reduces the loss rate of UDP datagram,thus realizing the reliable data transmission under the real-time operating system.