Atsuo Tachibana

Learn More
This paper presents a unique probing scheme and a rate adjustment algorithm that can be used for estimating the available bandwidth (ABW) of an end-to-end network path more accurately and non-intrusively. The proposed algorithm is based on the well-known concept of self-induced congestion and it features a unique probing train structure in which there is a(More)
Previous studies on inferring the origin of routing changes in the Internet are limited to failure events that generate a large number of routing changes. In this paper, we present a novel approach to origin inference of small failure events. Our scheme focuses on routing changes imposed on preferred paths of prefixes and not on transient paths triggered by(More)
We present a deployable scheme that achieves seamless handover in the context of heterogeneous wireless access networks based on concurrent multipath transfer (CMT) using the Stream Control Transmission Protocol (SCTP) with off-the-shelf Android smartphones and protocol translation servers. Since the scheme is accomplished by neither embedding special(More)
Since various types of wireless networks have been widely deployed, the Concurrent Multipath Transfer (CMT) scheme over multiple wireless networks has become vital to ensure that current mobile users can gain advantage in the context of high data transmission throughput and communication robustness. Aiming at deploying the CMT scheme, in this paper, an(More)
Available bandwidth (ABW) estimation in wireless networks is a critical issue for quality-of-service (QoS) provisioning. Nowadays, a network path often contains at least one wireless link e.g., mobile users having wireless connection to the Internet through laptop PCs or smartphones. Most of the existing tools for measuring ABW have been developed and(More)
Since congestion is very likely to happen in the Internet, locating congested areas (path segments) along a congested path is vital to appropriate actions by Internet Service Providers to mitigate congestion. We propose a practical method to locate congested segments by actively measuring end-to-end packet losses on appropriate paths from multiple origins(More)
A practical method of locating congested segments on the Internet by periodic end-to-end packet delay measurements along multiple paths is presented. This method is a network tomographic approach based on a clustering technique that effectively tackles the correlation among delay variations. Since the Internet is still highly prone to performance(More)
Since congestion is very likely to happen in the Internet, locating congested areas (path segments) along a congested path is vital to appropriate actions by Internet Service Providers to mitigate or prevent network performance degradation. We propose a practical method to locate congested segments by actively measuring one-way end-to-end packet losses on(More)