Fundamental Research on Universal Ad Hoc Network

自组织网络作为21世纪的信息基础设施有望得到发展。本研究的目标是开发一种通用的自组织网络，称为下一代自组织网络的通用自组织网络。在一个通用的自组网中，移动终端之间通过直接通信和多跳通信进行通信。首先，我们综述了自组网技术的现状和存在的问题。作为通用自组网的一种应用，我们提出了开放社区网络的概念。开放式社区网络是一种基于无线多跳技术的新型社区信息基础设施。作为开发通用自组织网络的案例，我们提出了无线局域网的新概念，即无线多跳局域网(WMLAN)。我们还利用IEEE802.11b无线局域网和PC机开发了实验系统，并对网络性能进行了评估。为了开发一种发现公共节点的方法，我们提出了一种使用分簇算法的高效分组洪泛方案和一种不使用控制分组的高效分组传递方法。为了开发一种高效、可靠地将信息传输到公共节点的方法，我们提出了一种用于下载信息存储通信端口的信息访问方法。为了开发一种在通用自组织网络中共享信息的方法，我们使用Gnutella开发了一个自组织网络实验系统。我们还对Gnutella的性能进行了评估。这些结果是实现通用自组网的基础技术。我们未来的问题是改善WMLAN和应用。

Development of ad hoc networks is expected as an information infrastructure in 21st century. The objective of this research is to develop a general-purpose ad hoc network, termed "a universal ad hoc network" as a next generation ad hoc network. In a universal ad hoc network, mobile terminals communicate with each other by using a direct communication and multi-hop communication, First, we surveyed current technologies and issues in ad hoc network technologies. As an application of a universal ad hoc network, we proposed the concept of an open community network. An open community network is a novel information infrastructure for local communities based on wireless multihopping technologies. As a case study for developing a universal ad hoc network, we have proposed a novel concept of wireless LAN, that is, Wireless Multihop LAN (WMLAN). We also have developed the experimental system using IEEE 802.11b Wireless LAN and PC and evaluated the network performance. To develop a method for discovering the public node, we have proposed an efficient packet flooding scheme using clustering algorithm and an efficient packet delivering method without using control packets. To develop a method for transmitting information to the public node efficiently and certainly, we have proposed an information access method for downloading information storing Communication Port. To develop a method for sharing information in the Universal Ad hoc Network, we have developed an experimental system of ad hoc network with Gnutella. We also have evaluated the performance of Gnutella. These results are fundamental technology for realizing universal ad hoc network. Our future problems are to improve the WMLAN and applications.