The Study Of Network Testing Instruments Based On Ethernet

The study and realization of programmable network testing instruments based on TCP/IP interface are described in this paper. The author analyzes the way of using TCP/IP interface , the software LabVIEW and the Standard Commands for Programmable Instruments(SCPI) to reach the aims of sharing the hardware and software resource and building various opening universal testing systems fast and convenient which base on commercialized hardware and software platforms.This network testing system is mainly made up of basic elements such as sensors, data acquisitions, network interface, display, universal computer software and hardware, etc. In order to meet the systematic designing requirements, the opening and modularize design is adopted in the whole hardware while the work of configuration and control are provided through software. The software adopts modularize, hierarchical design. According to characteristic and function of the whole system, the design is mainly divided into 4 pieces of module which are TCP/IP module, data acquisition module, display module and LabVIEW module. TCP/IP module again among them is divided into 6 parts which are Network card driver layer, ARP layer, ICMP layer, UDP layer, IP layer and TCP layer.As the control interface of the instrument, LabVIEW links the computer and instrument hardware through the application program. And it also carries on the works of signal analyzing, data acquisition, data storage, various figures display, etc, through the powerful data analysis handling capacity of thecomputer to reach the purposes of using software to express hardware , reducing cost of system and strengthening systematic function and flexibility .Finally , a programmable network testing instruments which based on TCP/IP interface , Lab VIEW and the Standard Commands for Programmable Instruments(SCPI ) is accomplish in this design. This system realizes the automatic testing of parameters in power network such as voltage, current, power factor ,etc. And many other parameters which used in various ways such as pressure, temperature and hydraulic level can also be tested by using this system. It really provides a way of reducing testing cost, strengthening the systematic flexibility and improving testing efficiency.