Research And Implementation Of The Communication System Used In The Value-added Service System For The Bank

The Value-added Service System for the Bank is a platform setting up between POS and the bank's host computer, providing some other exchanging services except for the traditional currency payment. The communication system of it includes the front-end system and the value-added service POS system. The former, responsible for data pre-processing including network communication, message authentication and data format changing, is a communication hinge that demands high throughput, strong retractility, as well as the security of the exchanging data. While the latter is the communication terminal, whose function includes not only the same data pre-processing as in the front-end system, but also the necessary business logic.The communication system's security and efficiency is the guarantee of the whole system. Aiming at the implementation of the communication system, on the analysis of the encryption standards in financial exchange and concurrent server, this paper has done the following:(1) Designation of the functions of the front-end system, the most important of which is communication protocol and security strategy. This paper implements the protocol extending ISO8583, and designs data encryption and key administration strategy based on ANSI X9.9, ANSI X9.8 and 3-DES.(2) Optimization of the performance of the front-end system, using the two dial numbers model instead of the traditional one dial number model to alleviate the burden and reduce the complexity of the system; using JNI to make the native methods responsible for the complex computing, thus enhance the computing speed; using thread pool in the implementation of the server, optimizing the usage of the system resource, improving the capability of dealing with large numbers of requests.(3) Development of the value-added service functions under the developing environment provided by the STAR 690 POS system, embedding them in the traditional POS function, making them run in phase with the front-end server.A secure and efficient front-end system and communication terminal are implemented in this paper, which provides the communication environment for the value-added service system.