Design And Implement An Online Securities Trading System

Online Securities Exchanging is a new type of Securities Exchanging method, with which, investors can access online entrustment service provided by Security brokerage companies, and can receive marketing quotes and marketing information. Online securities exchanging is low cost, easy to use and not restricted by user's location. The quantity of online exchanging increases 20% every year, due to the advantages of online securities exchanging. It is an important task for a Securities brokerage company to build up a secured, efficient online securities exchanging system.So the study of how to design and implement a secured, efficient online securities exchanging system has practical value. On the other hand, the technologies applied in the online securities exchanging system cover a wide range. For example, network connection, network security, load balance, etc. These technologies are also applied in other IT projects, such as E-business projects. So the study has the value for reference.In the study, the author draws comparisons between number types of technologies and presents his plans to improve them. His solution uses digital certificates to authenticate the identities of both the exchange participants, applies digital sign to prevent the sensitive data from being tempered, and encrypts data before sends it out to keep away unauthorized access; the author's design of the system network not only uses professional firewalls, but also implements hardware isolation systems to enhance the security. The author introduces a multi-trade-center network topology to improve the system's network reliability.The author analyses several types of load balance technologies, then designs an innovative load balance solution that combines the functions of the client software and the service application. The new load balance solution realizes a fault detection component at application layer to achieve dynamic fault tolerance at per-server granularity, and enables global load balance, service location transparency and service number transparency. Due to the load balance solution, the system possesses of linear expansibility.The author upgrades the system capacity not only with the help of new designed load balance system but also via the more direct way — to improve the efficiency of the single service application. The author studies three types of concurrent software architecture, and sums up several techniques to design high quality concurrent network application, such as event-driven software architecture, overlapped I/O operation, the OS's asynchronous I/O service, scoped locking and thread-safe interface,etc.The author provides system logical design, including conceptual design, load balance system logical design, module's function design, security and authentication architecture design, the design of the flow ofdata transferring, encryption and decryption, the design of the flow of entrust transaction, the design of the flow of account inquiry transaction, the design of the flow of quote inquiry transaction and the network design. The author weighs the tradeoff between different hardware platforms and Operating system, and makes the decision to select the type of hardware platform and OS to use in the system.At the last of this paper, the author analyzes the solution, and points out the strength and weakness of the system.