Astudy of peerto-peer multicast communications with multiple Internet interfaces

在这一年中，我们已经实现了PeerCast的动态路由改变功能，这是作为本研究中的对等通信的中间件，以优化路由，同时继续通信，因为PeerCast通常不能产生最佳路由。然后，我们研究了使用Web技术的多媒体分发系统，其形式为数字图像卡显示，该数字图像卡显示回放远程讲座和视频会议的每个场景，其中一个场景为高分辨率数字静止图像和演讲者的声音，由于安全漏洞，高通信负载，并且降低了使用指定软件进行对等多媒体通信的可用性。在今年，我们已经实施了这一系统，并通过其应用于我们部门的几个讲座进行评估，其中的有效性是通过提高学生的理解来证实的。此外，我们还实现了在无线网状网络的高响应的多媒体分发系统，通过将Web缓存到网状路由器。无线网状网络已被研究作为一个平台，通过在现场分配多个无线路由器，提供这种多媒体系统的无处不在的环境。我们提出了由昂贵的高性能路由器和廉价的低性能路由器组成的两层网状网络架构，以实现灵活性，可扩展性和可访问性，其中具有多个网络接口的可信主机可以成为前路由器。为此，我们实现了主机认证功能、多通道功能和IP地址分配功能。

In this year, we have realized the dynamic routing change function for PeerCast, which is adopted as the middleware for peer-to-peer communications in this study, in order to optimize the routing while continuing communications, because PeerCast usually cannot produce the optimal routing. Then, we have studied the multimedia distribution system using the Web technology by the form of the digital picture-card show that plays back each scene of a distance lecture and a video meeting with the combination of a high-resolution digital still image and a speaker's voice for one scene, due to the various problems of security holes, high communication loads, and degrades of usability in using designated software's for peer-to-peer multimedia communications. In this year, we have implemented this system, and evaluated it through its applications to several lectures in our department, where the effectiveness is confirmed by the contribution to the improvement of understandings of students. In addition, we have realized the multimedia distribution system with high response in the wireless mesh network by incorporating Web cashes into mesh routers. The wireless mesh network has been studied as a platform to provide the ubiquitous environment of this multimedia system by allocating multiple wireless routers in the field. We have proposed the two-layer mesh network architecture composed of expensive high-performance routers and inexpensive low-performance routers to achieve the flexibility, the expandability, and the accessibility, where trusted hosts with multiple network interfaces may become the former routers. For this purpose, we have implemented the host authentication function, the multiple channel function, and the IP address assignment function.