Research And Design On Structure Of Embedded Web Server

Embedded Web server can provide powerful support to remote monitoring. Transplanting embedded Web server in being and independent development are regarded as the main way to obtain embedded Web server. Embedded Web server in being are of fixed function, but have many advantages such as good quality of software, simple process of transplantation, abundant data, and open source. The most advantage of independent development is flexibility. It can be customized according to the actual situation. But software quality is difficult to guarantee due to technical and time constrains. It can bring potential safety hazard to the future use.Firstly, this paper starts research on embedded Web server in being. In order to understand the work process and to lay a good foundation for future maintenance and improvement, in-depth study focuses on the structure of GoAhead and Boa. On this basis, a small Web server has been designed by independent development. This Web server has a simple function and can only handle the request of static pages and CGI, but take an important step to the independent development of embedded Web server. Secondly, in order to improve data display of remote monitoring, dynamic history curve has been adopted. It can vividly reflect the trend of the data and be conducive to the monitoring of equipment. To this end, this paper designs two methods to solve this problem. Method one: JavaScript combined with VML. The client side can get data from Web server by Ajax, and draw dynamic history curve by VML combined with JavaScript. This method is complicated and needs the support of IE. Method two: using Applet. It fulfills data acquisition and curve display. The data obtained is the same as the method one. They both request a CGI program which generates an integer from 0 to 100. This method is simple, but needs the installation of JRE on the client side. The experiment shows that the two methods achieve the desired effect.