Research And Implement Of Embedded Web Server Used In Intelligent Remote Control System Of Home Electrical Devices

With the rapid development of the technology on embedded system and Internet,electrical apparatus in home is becoming more intelligent.The teli-monitoring system using in it will become the focus of research.In this background,The paper discussed an way of create this system base on embedded Web server and do some study focus the embedded Web server in the monitoring system and completed the coding and debugging of this Web server.Nowadays,there is lot's of research focus on the embedded Web server of the monitoring system showing in other papers,however a majority of those research have ignored the circumstance using in practice ,so their research or design could not be used in practice with those shortage.This paper has sum up those shortage to two factor:(1) security. Verification to users is necessary to monitoring system.Verification is incapable via making an server page with the form about verification simply,because the attacker can capture the verification information while account and password is transmited on Internet or change it before the message get to the receiver. It's very awful that attacker will have the chance to control the legal user's electrical apparatus by this way.If we encrypte the message before send it to the net,the attacker will only be able to capture the cryptograph,who can't threat the security of the system.Using cryptograph in the Web server could enhance the security of monitoring system,but lot's of papers didn't do this.(2)System cost.Capability of the embedded system is far less than personal computer or mainframe computer,so the task over embedded system must take the system cost into account.How to cut it down is the research point abroad.There are only a few research on system cost in majority of other papers.Much of them only great the Web server in monitoring system base on Boa which is an popular embedded Web server used abroad,but Boa which is only an general embedded Web server is not suitable to be used in monitoring system at home.There are lot's of shortage need to be improve to Boa.For example,Boa create a new process to run the dynamic server page base on CGI,while creating a new process will cost much of system resources.Aim at these shortage,this paper table two proposal about the improvement on embedded Web server used in monitoring system to electrical apparatus home.(1)In the aspect of security,this paper use SSL protocol to create the secure channel between client and server in embedded Web server.(2)In the aspect of system cost,this paper has analysed kinds of techniques used in embedded Web server compared with Boa,and point out their strongpoint and shortage and how to improve them.This paper has completed an embedded Web server named Myserver,base on pipelining and multi-threads server mode and the method of running dynamic server page with shared lib.Myserver's excellence capability showed in test report has justify the method in this paper.Tasks completed in Myserver is showed in next four points:(1)Create the truss base on pipelining and multi-threads server mode, include five kinds of server threads and five key data queues;complete the server function that supply the static Web page to client.(2)Complete the secure link channel between client and Web server base on SSL.(3)Create the interface between Web server and peripheral shared lib as server page which has the functions such as monitoring to devices;provide API to programmer who will use the funcitons in this interface.(4)Complete the functions include session,cookie,file-upload and dealing with GET or POST Form to consummate Myserver.At last,this paper has do some stress testing on Myserver and Boa,and compared their service capbility from two sides according the data from the test report.(1)At static server page,Myserver's capbility is almost the same to Boa's.Boa's capacity less stronger than Myserver because Boa uses I/O multi-use to deal with parallel request.I/O multi-use is faster than multi-thread.(2)At dynamic server page,Myserver is at least three times faster than Boa.Because Myserver deal with the dynamic server page in thread while Boa in new process.Dealing with dynamic server page is more frequent than dealing static page in monitoring system.So the capability in dealing with static page.dynamic page is more important than in static.So Myserver is much more compatible to be used in monitoring system than Boa for its excellence capability in dealing with dynamic server page.In conclusion,the work in this paper is much valuable in the field of information appliance.