Seamless User-Level Handoff in Ubiquitous Multimedia Service Delivery
Seamless User-Level Handoff in Ubiquitous Multimedia Service Delivery
复制标题
无处不在的多媒体服务交付中的无缝用户级切换
DOI：
10.1023/b:mtap.0000011932.28891.a0
复制
发表时间：
2004
影响因子：
3.6
通讯作者：
Dongyan Xu
中科院分区：
文献类型：
--
作者：
Yi Cui;K. Nahrstedt;Dongyan Xu
先进的移动的计算技术正在实现“无处不在的个人计算环境”。在本文中，我们专注于在这样的环境中的一个重要问题：用户移动性。在用户移动性的情况下，用户可以通过任何可能的移动的/固定设备在任何时间、任何地点自由地访问他/她的个性化服务。在这种情况下提供移动性支持带来了一系列挑战。最基本的问题是，即使访问主机或服务提供商发生变化，也要保持用户对相同服务的访问。现有的系统级移动性解决方案不足以解决这个问题，因为它不知道应用程序的语义。另一方面，使每个应用程序都具有移动性感知将大大增加开发开销。我们认为，中间件层是解决这个问题的最佳场所。一方面，它知道应用程序语义。另一方面，通过在中间件层中构建应用程序中立的移动功能，我们消除了使每个应用程序都具有移动性的需要。在本文中，我们设计了一个中间件框架，以支持用户的移动性在普适计算环境。它的主要移动功能包括用户级切换管理和跨异构计算平台的服务实例化。我们使用原型中间件系统验证了主要的移动功能，并在两个多媒体应用程序（移动的视频播放器和移动的音频播放器）上测试了它们。为了最大限度地接近现实世界中的用户移动性的情况下，我们已经进行了各种计算平台和通信模式的实验，从T1连接的高端PC与无线网络的手持设备。结果表明，我们的中间件框架是能够提供有效的用户移动性支持在异构计算环境。
Advancing mobile computing technologies are enabling “ubiquitous personal computing environment”. In this paper, we focus on an important problem in such environment: user mobility. In the case of user mobility, a user is free to access his/her personalized service at anytime, anywhere, through any possible mobile/fixed devices. Providing mobility support in this scenario poses a series of challenges. The most essential problem is to preserve the user's access to the same service despite changes of the accessing host or service provider. Existing system-level mobility solutions are insufficient to address this issue since it is not aware of the application semantics. On the other hand, making each application to be mobility-aware will greatly increase the development overhead. We argue that the middleware layer is the best place to address this problem. On one hand, it is aware of application semantics. On the other hand, by building application-neutral mobility functions in the middleware layer, we eliminate the need to make each application mobility-aware. In this paper, we design a middleware framework to support user mobility in the ubiquitous computing environment. Its major mobility functions include user-level handoff management and service instantiation across heterogeneous computing platforms. We validate the major mobility functions using our prototype middleware system, and test them on two multimedia applications (Mobile Video Player and Mobile Audio Player). To maximally approximate the real-world user-mobility scenario, we have conducted experiments on a variety of computing platforms and communication paradigms, ranging from T1-connected high-end PC to handheld devices with wireless networks. The results show that our middleware framework is able to provide efficient user mobility support in the heterogeneous computing environment.