VxWorks-based Software Bus And Autonomous Recovery Techniques

Fault-tolerant technology is widely used to improve the reliability of embedded systems. Hardware fault-tolerant technology is limited and hardware maintainability is poor, so fault-tolerant technology for hardware failures and software faults is more and more to be achieved by software fault-tolerant. With the development of embedded system technology the system is close to the large and comprehensive, so, the increasingly complex but reliable real-time software system is needed. VxWorks that is a high-performance, real-time and reliable embedded operating system is often used as the operating system for embedded systems. How to design autonomous recovery management software based on the VxWorks operating system which is for achieving fault-tolerance and has high reliability is a serious problem.The paper foucus on the features of embedded systems and VxWorks, software bus architecture, autonomous recovery model and other related research.The research content is as follow:(1) A better way of system architecture is required in system because of the Volatile demand of embedded systems, the tailoring of software system and the security requirements of software architecture. Component-based software bus architecture is proposed. In the design of autonomous recovery management software architecture, the resource use layer is designed by packaging the resources in VxWorks operating system by software bus, which forms a layered software architecture. The efficiency of development is improved by component reuse technology which is used to design the autonomous recovery components. the architectural approaches which is used to design and development of autonomous recovery management software could support the rational use of operating system resources and provide a good schedule.The software bus which is designed in this paper more emphasis on the underlying communication platform, in the bus the signal mechanisms and shared memory mechanism is from the underlying library functions of VxWorks operating system, so, compared with the communication function which is designed by the software developer, the bus software of this paper has better security and reliability. Combined with the ORB-based software bus, the software bus is designed in this paper has obvious advantages in the utilization of resources and the dependence of the TCP/IP protocol.(2) The system can shielding failure so that the right services of the system is provided when the fault is found by introducing the redundant resources, which make the run time of the system is extended. This paper presents three kinds of redundancy schemes which are cold backup, hot backup and dual-redundant, and combined with the characteristics of the common fault, monitor mechanism and dynamic reconfiguration mechanism in three kinds of sheme are designed in the paper. Because of the variability of the requirements of autonomous recovery, different redundant architecture is produced, so the autonomous recovery technique should be expanded easily. Based on the above, on the basis of studying the demand of the autonomous recovery, the basic fault-tolerant components are designed, and component reuse technology is introduced into the design of autonomous recovery architecture based on the software bus, the self-recovery component is produced when the basic fault-tolerant components are combined according to the certain combination strategies depending on the characteristic of certain redundant architecture to and provides the self-recovery service for the business components.