Study And Realization Of Android-based Instant Messaging System

With the rapid development and integration of mobile communication and Internet,GPRS wireless networks making high-speed access to the Internet becomes reality and mobile users can enjoy services provided by Internet.Instant messaging is based on applications of Internet protocol,which can enable users to use different devices to communicate.And with the constant popularity of mobile phones as well as the continuous performance improvement,it is time for real-time communication systems to transplant from the traditional PC-Mobile. Additionally,in the market of China's huge mobile phone users,mobile phone users using of instant messaging software is increasing.Currently, mobile operating systems are too closed,and the major instant messaging software communication protocols used are not unified.Android is based on the open-source Linux mobile operating system platform,and XMPP is a XML-based open-source instant messaging protocol,so Android and XMPP-based instant messaging systems have good application prospect.In this paper,first of all,a systematic study of the background on the current mobile operating systems is introduced.Then the states of mobile operating system,instant messaging software and instant messaging protocol's development are simply described.Furthermore,the characteristics,architecture,composition and working mechanism of Android are analyzed in detail.Finally,the advantages of Android are instructed through comparison with other mobile operating system.This paper puts forward a detailed System architecture and the solution of system server side and client side.Using open-source Openfire as a system of instant messaging platform realizes client-side instant messaging.The module composition of the system client-side is introduced,and XMPP instant messaging protocol and the communication mechanism of the system are analyzed.Aimed at the current security problems of communication data and the characteristics of the system,data encryption algorithm IDEA has been improved,also A-IDEA algorithm is designed,as well two algorithms are compared from several aspects.For the image file encryption,the schema is to adopt A-IDEA and RSA algorithms combined.Running Processes of the server are analyzed.In addition,the system client's side is designed and realized in detail.Finally,the system is deployed and tested.