The Research And Design Of Portable Network Fault Diagnoser

Network monitoring is one of the necessary means to maintain network's normal operation. The important content of network monitoring is the data acquisition and fault diagnosis for network devices. With the growing scale of computer network, due to the limited capacity of complicated operations, traditional network diagnosis system has been unable to meet the demand of intelligent and automatic diagnosis. In addition, it is unrealistic to prepare high- performance intelligent diagnosis system for each individual network. People need one kind of network fault diagnostic equipment with features of cost-effective and easy to move. Therefore, this paper studies about the design of portable network fault diagnoser.The paper first analyzes the functions that the portable network fault diagnoser should have, according to which scheme of the diagnoser is designed. It choses the development board as the hardware, selects the Qt/Embedded as the graphical interface library of the diagnosing application, selects QtCreator1.3 as the software's integrated development environment. Then theoretical research from three aspects is made for specific design the network fault diagnoser, which is the system structure, network characteristics' acquisition and fault diagnosis algorithm.The dual-independent system link model put forward by this paper has two independent link system, which are the network system and serial bus system. When the network doesn't work because of some serious fault, the diagnostic device can continue to collect the characteristics of network equipment to ensure the validity and sustainability of the network's diagnosis through the serial ports, which can improve the robustness of network system diagnosis. The proposed self-adaptive dynamic polling algorithm based on SNMP, which considers the situations of network transmission conditions and the agents' loads, can reduce the network bandwidth's usage, and also reduce the load of the agent. As the resource-constrained character of the embedded system, it can not run a large-scale intelligent diagnosis algorithm with high complexity degree. The multi-levels fault diagnosis algorithm proposed combining the simple diagnostic rules and the intelligent diagnosis algorithm, not only meets the software's resource requirements, and the diagnostic results has the timely and comprehensive features.After the foregoing work, the application of the portable network fault diagnoser is carried on. It adopts the modular approach to design the application's function module such as the main interface, the network self-test, and single detection, etc. Meanwhile, the back-end database of devices on network is also designed. Then, the paper carries on building the embedded Linux system, including the root file system's build, kernel porting and BootLoader porting. The detailed operational methods and procedures is given.Finally, the paper constructs a simulated environment to test the portable network diagnoser. The testing results show that the design has achieved the aim.