【作者】 彭亮；

【导师】 王国军；

【作者基本信息】 中南大学 ， 计算机科学与技术， 2014， 硕士

【摘要】 摘要：移动互联网的高速发展使得人们的网络生活开始从桌面终端向移动终端迁移,即时通信作为目前的互联网的核心应用之一,在移动设备上被广泛使用。即时通信协议XMPP协议基于XML语言,不仅能够支持异构系统之间的互联互通,且具有很强的可扩展性而被认为是未来即时通信领域的主流协议。但XMPP协议本身是一个高耗能的协议,将其应用于移动设备上时,会给电池的续航能力带来较大的挑战。论文针对XMPP协议在移动设备上的场景,提出一种出席消息代理模型,通过代理服务器缓存出席更新消息,并根据缓存策略调整消息到达设备的时间序列,避免设备长时间处于耗能较高的状态下工作,从而节省电池电量。由于出席消息代理会给出席消息带来一定的延迟,延迟时间越长节省电量越多,但长时间的延迟将导致较差的用户体验。论文通过排队论建立了数学模型,推导出延迟和省电量之间的关系,并通过实验进行验证。实验表明,无论移动设备上登录单个还是多个XMPP客户端,出席消息代理都能够有效节省设备电量,特别在3G网络下客户端节省电量甚至达到56.5%。其次,结合XMPP协议架构的特点,本论文提出了一种基于XMPP协议的实时消息推送方案,并研发出移动医疗推送系统。该系统是由中南大学信息科学与工程学院与湘雅医院合作,能够为用户提供体检报告、门诊结果、住院费用等医疗信息的实时推送与历史记录查询。系统不仅能够节省用户时间,同时也能缓解医院的接待压力,具有一定的实用价值。图21幅,表14个,参考文献61篇。更多还原

【Abstract】 Abstract:With the rapid development of mobile Internet, the mode people use the Internet has gradually changed from the desktop terminal to mobile device. Meanwhile, instant messaging, as one of the current Internet core applications, is widely deployed on mobile device. XMPP (Extensible Messaging and Presence Protocol) is a kind of instant messaging protocol, which is based on XML. Not only can XMPP support the communication between heterogeneous systems, but also it is considered to be the mainstream protocol of the future instant communication area because of its high expansibility. However, XMPP is also a high energy consuming protocol. If it is applied to mobile devices, it will bring great challenges to the battery life of these devices.This thesis proposes a presence proxy model in view of the application scenario that XMPP is applied on mobile devices. In this model, messages is updated through the cache of the proxy server and the time sequence of the arrival messages of these devices is adjusted constantly according to the caching policy so that the device can avoid working under a high energy-consuming state for a long time and save the battery power. Because the presence proxy server causes some delay for the attending message, the longer the delay is, the more power can be saved. However, too long delay will result in a poor user experience. This thesis proposes a mathematical model on the basis of queuing theory and deduces the relationship between the message delay and the power saving. In addition, all of the propositions are verified by experiment. Experiment result shows that the presence proxy model can save the power effectively for a single XMPP client or multiple XMPP clients on mobile devices, especially for the3G network client that can save56.5%of the power.According to the characteristics of XMPP architecture, this thesis proposes a real-time message-pushing scheme based on XMPP. Besides, a mobile medical message-pushing system is developed by School of Information Science and Engineering of Central South University and Xiangya Hospital. This system can provide the users real-time message pushing and record inquiry services for medical examination report, diagnostics results and hospitalization expense. It is turned out that this system can save time for the users and alleviate the pressure for the hospital reception capacity to a certain extent.更多还原