The Study In Immediate Communication System Based On UDP Protocol

The network communication technology applied in the field of modern science and technology gets deepening and the demand for net communication gets rising due to the high-speed development of modern information technology, so that a good immediate Communication System is necessary to meet the growing demand of users for the network coding. Based on this background, this article researches and designs an immediate communication system base on UDP protocol.Firstly, this article researches the TCP/IP/UDP protocols, analyzes the function of the five layers architecture in TCP/IP and several conception about IP protocol. Then particularly analyzes the differences between TCP and UDP protocol and determines the reason for using UDP protocol in this article.Secondly, it researches the knowledge about Windows network programming including the basic conception and programming principle of Winsock, frequently used function and models of datagram socket programming, MFC network programming class.After researching the message-response mechanism of MFC and the multi thread technology, according to the design requirements and function to be realized on the server, the overall framework model is confirmed.The immediate communication system produced in this article is compiled in VC software environment to implement the system by making use of the modular software thought to design, based on the p to p mode. After the whole model of the system is designed, this article describes several models including connecting to the internet, sending and receiving messages, sending and receiving files in detail. Furthermore, improves the function of the system, adds the function of capturing screen, scanning the net segment, displaying to the tray and so on. Finally, tests the whole system and the test results are analyzed.With systematically researching the overall flow to design the immediate communication system to deepen the understanding for communication software design and realization, the article has some theoretical and practical significance for designing the system with powerful improved function in the future.