Studies on the mechanisms of traffic management and control required for the deeper Internet

本研究主要研究了更深层的互联网所需要的流量管理和控制机制，取得了以下研究成果：1）网络断层扫描测量网络特性的基础研究：由于精确的分组延迟信息对于理解网络特性是非常有价值的，因此开发了从部分测量中推断延迟相关信息的方法，如从端到端路径测量中推断每个流的排队延迟统计和每个链路的排队延迟方差。我们也证明了非常精确的时间戳在网络测量中的有效性。2）多类QoS路由的基础研究随着网络应用的日益多样化，Internet提供各种服务已经变得至关重要。我们提出了一个分布式的链路状态QoS路由与不同的链路成本获得多个路由表，以有效地适应多类流量。从我们广泛的模拟结果中，我们发现， 关于我们 3）移动的网络中无线资源有效利用的基础研究对于由无线局域网（WAN）组成的移动的网络，我们提出了一种分散的接入点选择结构，以有效地利用无线接入资源，以及一种动态的网关选择方案，用于无线mesh网络中的负载均衡。此外，为了实现由不同IP地址组成的WLAN之间的无缝切换，已经提出了基于帧重传次数的切换管理器。我们已经证明了这些方法的有效性。4）流量控制机制的基础研究，在响应突然的流量变化：为了提高排队延迟性能的流量控制，一种方法，动态分配的流量的边缘路由器的基础上，流量测量和主动丢弃数据包的方法，中间路由器的基础上，所实施的应用程序特性的允许延迟限制。少

In this research, we have studied the mechanisms of traffic management and control required for the deeper Internet.Research results are the following.1)Fundamental studies on the network tomography to measure network characteristics :As precise packet delay information is valuable for understanding network characteristics, methods of inferring delay-related information such as per-flow queuing delay statistics from partial measurements and per-link queuing delay variance from end-to-end path measurements have been developed. We also have shown the effectiveness of very precise time-stamp in network measurement.2)Fundamental studies on multi-class QoS routingWith the increasing diversity of network applications, it has become crucial for the Internet to offer various services. We propose a distributed link state QoS routing with multiple routing tables obtained upon different link costs to effectively accommodate multi-class traffic. From our extensive simulation results, we found that … More the proposed scheme is successful in improving performance.3)Fundamental studies on effective utilization of wireless resource on mobile networksAs for the mobile networks consisting of wireless LAN (WAN), we have proposed a decentralized access point selection architecture in order to use the wireless access resources effectively, and a dynamic gateway selection scheme for load balancing within wireless mesh networks. In addition, to achieve seamless handover between WLANs consisting of different IP subnets, a handover manager based on the number of frame retransmissions has been proposed. We have shown the effectiveness of these methods.4)Fundamental studies on traffic control mechanisms in response to sudden traffic variations :For improving queuing delay performance by traffic control, a method for dynamic assignment of traffic flows to multiple upper-paths by edge-routers based on traffic measurement and a method of proactively discarding packets by intermediate-routers based on the allowable delay limit enforced by the application characteristics have been developed. Less