Tax Control System Design And Implementation, Of Security Mechanisms

The tax revenue is the important foundation of economic construction and the social development. And the invoice is the main basis that our country levies taxes. But because of the dispersiveness of the use of invoice, the revenue department is unable to be good control to the invoice. That causes the generous loss of the state revenues. In order to solve this difficult problem, we have implementation the tax-controlled system. That can control each one to trade in taxpayer's business activities, reach possible improve the manage efficiency, strengthen the source of tax revenue, reduce the tax avoidance. In the tax-controlled system, security of data is the most basic demand of the whole system. In our system, regard PKI as the safe foundation, regard CPU card as the control of the security, regard POS machine as the safe operating platform. Combine the tax-controlled application system to ensure the systematic data security. At first, I have carry on the research of the security of the data in this article, and have analyzed PKI technology, CPU card technology and encrypted algorithms especially. I have studied how to application CA authentication, digital signature and confirm taxpayer's identity in the tax-controlled system. And how to utilize CPU card security system and file structure to guarantee the security of the data, how to use different keys to carry on authentication and encrypt in different instance. Second, we design and implementation the tax-controlled system and whole security of data of the system. We integrate application the encrypted algorithms technology, digital signature, key managing and digital digest, etc. And combine such hardware equipment as CPU card and POS machine, has solved the systematic security wholly. In this system, fully utilize DES algorithm and RSA algorithm, according to tax-controlled machine's number, taxpayer number and branch office code produce the DES key, public key and private key. This system keeps these keys to tax-controlled card. The key is used in the authentication of the card and POS machine. The private key can be used in the digital signature of the detail of invoices. The detail of the invoice is encrypted with MAC technology, and keeps MAC yard in the POS machine and types on the invoice. The MAC yard can be used in the checking of the tax bureau. Finally, according to the analysis on safe practice and design of the whole system, introduce the implementation of the POS machine. Including user interface gather data, through the upper-machine analyze data and send to POS machine. The POS machine carried out the function module and returned the result finally.