Research And Realization Of Embedded SNMP Agent For Manufacturing Equipment Management

With the expansion of production scale, the production resources optimization andcost control are more and more concerned by the manufacturing enterprises andAcademia. As one of the most important production resources for the manufacturingenterprises, the production equipment is characterized by decentralized deployment andlarge varieties, which make the networked real-time dynamic management forproduction equipment become a pressing demand of the manufacturing enterprises. Butmost of the equipments in the production field do not support Ethernet communication,which are difficult to gain access to enterprise management network, that causes theproduction equipment can’t be effectively managed by enterprise in real time.Simple Network Management Protocol(SNMP) is specifically designed for theimplementation of network management based on Internet. Its network managementframework of Manager-Agent can implement network management for non-IPequipment. Because the SNMP agent is responsible for real-time information interactionwith the field equipment, its performance directly affects the structure and costs of theSNMP management system. Therefore, this paper proposes building embedded SNMPAgent based on Linux for manufacturing equipment management after analysis of itsdemand for SNMP agent. Then, the paper emphasizes on three key technologies ofbootloader, embedded Linux operating system and SNMP Proxy Agent in building theAgent.Firstly, the function of embedded SNMP Agent is designed on the basis ofanalyzing the mechanism of U-Boot booting and generality implementation,furthermore the key issures in transplantation U-Boot is researched. Aiming at theproblem that U-Boot does not support booting from the large page Nandflash and bothfrom two Flash, U-Boot is improved without changing U-Boot generally and thecompatibility is enhanced.Secondly, the Linux kernel is ported and graphically customized based on thedemands of embedded SNMP Agent for manufacturing equipment management.According to the hardware configuration of application system, the LCD and DM9000netcard device drivers are ported, meanwhile touch screen input and RS485devicedrivers are designed on the analyzing of the principles of Linux device driver. Combingthe characteristics of various types of embedded Linux file systems and hardware configuration of the application system, this paper designes the architecture of multiplefile systems and studies on the key problem of implementation and transplants theQt/Embedded of graphics support system.Finally, the SNMP Proxy Agent model for manufacturing equipment managementis given and three key factors of MIB library extension, protocol mapper and devicecommunication manager are examined with special attention. Then the detailed processof the proxy agent model initialization, request service response and productionequipment supervision is given. At last, a simulation system is built on the basis of thesystem integrated and functions of the SNMP agent is tested.