Research And Design Of Prepayment Vending System

Prepayment technology is used to solve the difficulty in collecting the fee of the public services,such as water,electricity,gas and heat.The level of this technique has been improved constantly in the past few years,it has produced gradually,and has formed a new industry.The appearance of prepayment meter not only realized the charge automation of used electricity,but also changed in electricity charges after the first of the unreasonable situation,made the electricity department can get part of the pre-charge and is conducive to the development of public utilities.But with the popularity of the promotion of products,systems attack prevention,anti-tracking performance of data security has always been an outstanding technical issue,if this issue is not resolved well and there exist technical problems,it is likely to cause the power sector to serious economic losses and make a negative impact on society.Data security is the most important technique problem of all the IC card prepayment product systems,but the majority of the IC card prepayment product systems on the current market haven't solved the data security problem perfectly.In this paper several topics are investigated:internal software design of the electric meter,the password security of the IC card,encrypting and checking the data on the IC card,the security of the database,and a novel comprehensive data security design scheme is proposed,so that damages by passive and active attacks can been avoided.The paper mainly dissertates with the software of the system—IC card prepayment management system,after briefly introducing the whole IC card prepayment products system,and detailed introduces the character of IC card. Through deep research in IC card password security technology,a method is proposed in this paper which use DES algorithm to generate a middle-code, prepayment vending system database and ammeter RAM store pseudo-code,then get Card code by operating on middle-code and pseudo-code to insure the security of the code of IC card;meanwhile,the step of data-encrypting would make the data of IC card much safer.By the means of the structural system analysis,the research,design and realization of the whole prepayment vending system is completed successfully. The paper can be divided into two parts:the former part introduces the national standards and technical indicators of prepayment meter,a brief introduction of the prepayment meter's hardware and software.The later part introduces the design and realization of the IC card prepayment vending system.It is based on relative database SQL Server 2000,and uses VS2005 as the platform of development.The object-oriented programming language C#.NET develops a Web-based prepayment vending system,which will realize the use of IC cards for pre-sale of electric energy meter and management functions,and friendly user interface,fresh menu window, strong control function are also provided to user.