Authorship：Lead author   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

DOI： 10.1007/s13160-020-00452-w

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Other Link： https://link.springer.com/article/10.1007/s13160-020-00452-w/fulltext.html

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

DOI： 10.1007/s13160-019-00382-2

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Other Link： http://link.springer.com/article/10.1007/s13160-019-00382-2/fulltext.html

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

DOI： 10.1080/25742558.2019.1660503

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

DOI： 10.1080/25742558.2019.1596552

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Other Link： https://www.tandfonline.com/doi/pdf/10.1080/25742558.2019.1596552

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

DOI： 10.1007/s13160-018-0333-9

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Other Link： http://link.springer.com/content/pdf/10.1007/s13160-018-0333-9.pdf

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.comnet.2018.01.049

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Institute of Electronics, Information and Communications Engineers (IEICE)  

DOI： 10.1587/transfun.e98.a.1637

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Institute of Electronics, Information and Communications Engineers (IEICE)  

DOI： 10.1587/transfun.e98.a.1602

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.comcom.2013.03.004

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Authorship：Lead author   Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Proceedings - IEEE Symposium on Computers and Communications  

Pre-congestion notification (PCN) is a packet marking mechanism for DiffServ domains to facilitate feedback-based admission control (AC) and flow termination (FT) for the Internet to achieve quality of service (QoS) for inelastic flows. While AC blocks new flows to prevent an overly high load on network links, FT removes traffic to protect the QoS of the remaining PCN-flows when traffic is rerouted due to any kind of failure. We focus on one of the PCN methods, the controlled load (CL) method, whose edge behavior is now under standardization in the PCN working group of the Internet Engineering Task Force. The CL method terminates a sufficient number of flows in one shot and seems to have accurate control. However, we discovered that more termination than was needed, which we call overtermination, occurred in the CL method. We found that the CL method causes overtermination when not all the ingress-egress pairs have the same round-trip time. A countermeasure is presented to remove this overtermination. © 2010 IEEE.

DOI： 10.1109/ISCC.2010.5546742

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Institute of Electrical and Electronics Engineers (IEEE)  

DOI： 10.1587/transcom.e93.b.2273

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Institute of Electrical and Electronics Engineers (IEEE)  

DOI： 10.1109/surv.2010.040710.00078

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Authorship：Lead author   Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IEEE International Conference on Communications  

We present a session initiation protocol (SIP) network design for a voice-over-IP (VoIP) network to prevent congestion caused by people calling friends and family after a disaster. The design increases the capacity of SIP servers in a network by using all the SIP servers equally. The design uses a property that SIP network elements do not carry voice data packets but signaling packets instead. Furthermore, the design achieves simple routing based on telephone numbers. We evaluate the performance of preventing congestion through simulation. We show that the proposed design has roughly 20 times more capacity, which is 57 times of the normal load, than the conventional design if a disaster were to occur in Niigata Prefecture. ©2009 IEEE.

DOI： 10.1109/ICC.2009.5199461

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Publisher：IEEE International Conference on Communications  

The topology of a network seriously affects its cost, reliability, throughput, and traffic pattern, etc, so we need to simultaneously consider these multiple criteria, which have different units, when evaluating network topologies. Moreover, we need to reflect the relative importance of each criterion when evaluating the network topology. However, ordinary methods of network topology design consider only a single criterion. In this paper, we apply AHP (analytic hierarchy process), which has been widely used when making a rational decision with multiple criteria, to network topology design. AHP enables us to reflect the relative importance of each criterion on the results. In network topology design, we need to consider a huge number of candidates, and the differences in the weights among candidates are small. Therefore, the optimum topologies will be determined by just the weighted criteria, and other criteria will not be considered. Therefore, to emphasize the difference of the weights, we propose to use a linear-transformed value of each criterion when constructing weights in AHP. ©2008 IEEE.

DOI： 10.1109/ICC.2008.393

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

Abstract

The paper introduces two new unicast active end‐to‐end measurement techniques, called the single–double unicast probing (SDUP) and the delay‐based unicast probing (DUP), to estimate the rate of losses which occurs on the shared network path of two flows. A comprehensive performance evaluation and a comparison between these two techniques and an existing one having the same objective, the striped unicast probing (SUP) (Proceedings of the INFOCOM 2001—The IEEE Conference on Computer Communications, No. 2, Anchorage, Alaska, U.S.A., 2001; 915–923), were carried out. We demonstrate that our proposed SDUP technique provides even better estimation accuracy compared to that of the SUP while it requires only one piece of measurement equipment at only one receiver instead of deploying units to both receivers. Furthermore, with only one sender and receiver pair we can measure not only one shared path, but any partial path that begins at the sender and is located on the sender–receiver path. We also show that while the DUP have the same accuracy as the SUP in the case of Drop‐Tail buffer management, the DUP is capable of measuring loss rates of RED buffers, which the other techniques do not work with. The SDUP and the DUP are less intrusive and cause less bursty traffic compared to the SUP. Finally, the adaptation of these techniques into passive measurements is also considered. Copyright © 2006 John Wiley & Sons, Ltd.

DOI： 10.1002/dac.839

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Proceedings of the Third IASTED International Conference on Communications, Internet, and Information Technology  

In this paper we present a new method for the detection of bottleneck link(s) in the networks. The proposed method is based on the variance-per-mean ratio of the flow's throughput crossing the link which can be calculated from the data trace information provided by passive traffic monitoring. This new indicator of bottleneck links is found to be effective and robust against the offered link loads, bottleneck bandwidth, and the traffic composition. The results are verified using both simulation and real measurement analysis.

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Authorship：Lead author   Language：English   Publishing type：Research paper (international conference proceedings)  

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Authorship：Lead author   Language：English   Publishing type：Research paper (international conference proceedings)  

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Language：English   Publishing type：Research paper (international conference proceedings)  

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Language：English   Publishing type：Research paper (international conference proceedings)  

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：The Operations Research Society of Japan  

DOI： 10.15807/jorsj.46.372

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Authorship：Lead author   Language：English   Publishing type：Research paper (international conference proceedings)  

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Language：Japanese  

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Language：English   Publishing type：Research paper (international conference proceedings)  

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Authorship：Lead author   Language：English   Publishing type：Doctoral thesis  

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

DOI： 10.1007/bf03167447

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Other Link： http://link.springer.com/article/10.1007/BF03167447/fulltext.html

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/s0140-3664(01)00309-7

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：IEICE Transactions on Communications  

We have developed a new traffic measuring tool and applied it to the real-time simulation of a network. It monitors IP traffic on an ATM link and continuously transfers the length and timestamp of each IP packet to a post-processing system. The post-processing system receives the data, estimates the cell's arrival epoch at the transmission queue of the ATM link, and simulates the queueing behavior on-line if conditions differ from those of the actual system. The measuring tool and real-time simulation represent a new approach to traffic engineering. A new estimation problem, the arrival sequence estimation, is shown and some algorithms are proposed and evaluated. Also, a new dimensioning algorithm called the queue decay parameter method, which is expected to be robust and applicable to real-time control, is proposed and evaluated.

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：The Operations Research Society of Japan  

DOI： 10.15807/jorsj.44.1

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Authorship：Lead author   Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Proceedings of the International Symposium on Software Reliability Engineering, ISSRE  

We propose a criterion to determine a more appropriate software reliability growth model in the early development phase. The criterion with a discrete software reliability growth model determines the absolute worth of a model because the discrete software reliability growth model perfectly reproduces the parameter estimates when the data are used as an exact solution of the equation. The values of the proposed criterion of a discrete software reliability growth model are smaller than those of another software reliability growth model in all periods during the test phase with actual data sets. The discrete software reliability growth models are described with difference equations which have exact solutions. The models yield accurate parameter estimates in spite of a small amount of input data in an actual software testing. Therefore, the criterion and discrete software reliability growth models enable us to predict in the early development phase when software can be released.

DOI： 10.1109/ISSRE.2001.989471

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IEEE International Conference on Communications  

We have developed a real-time simulator that is connected to the network on-line and continuously uses the monitored IP traffic on AAL5/ATM. The simulator is software running on a real-time OS in a PC containing ATM network interface cards, which can use the information provided by the timestamp, VPI/VCI, IP address, protocol number, and port number of the monitored packets for the simulation. The simulator provides a simulation model of a multiplexer whose output link speed, buffer size, and queueing discipline can be changed by the user. In addition, we propose a simulation server that makes a simulation platform easily available. The simulator enables us to identify the appropriate amount of network resources, such as link speed and buffer size, and the effectiveness of various queueing disciplines. Numerical examples using the simulator in a real network are also shown.

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：IEICE Transactions on Information and Systems  

I describe a software reliability growth model that yields accurate parameter estimates even with a small amount of input data. The model is based on a proposed discrete analog of a Gompertz equation that has an exact solution. The difference equation tends to a differential equation on which the Gompertz curve model is defined, when the time interval tends to zero. The exact solution also tends to the exact solution of the differential equation when the time interval tends to zero. The discrete model conserves the characteristics of the Gompertz model because the difference equation has an exact solution. Therefore, the proposed model provides accurate parameter estimates, making it possible to predict in the early test phase when software can be released.

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：IEICE Transactions on Information and Systems  

I describe a software reliability growth model that yields accurate parameter estimates even with a small amount of input data. The model is based on a proposed discrete analog of a Gompertz equation that has an exact solution. The difference equation tends to a differential equation on which the Gompertz curve model is defined, when the time interval tends to zero. The exact solution also tends to the exact solution of the differential equation when the time interval tends to zero. The discrete model conserves the characteristics of the Gompertz model because the difference equation has an exact solution. Therefore, the proposed model provides accurate parameter estimates, making it possible to predict in the early test phase when software can be released.

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Authorship：Lead author   Language：English   Publishing type：Research paper (international conference proceedings)  

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Language：English   Publishing type：Research paper (international conference proceedings)  

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Authorship：Lead author   Language：English  

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Authorship：Lead author   Language：English  

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Authorship：Lead author   Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (trade magazine, newspaper, online media)  

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Authorship：Lead author   Language：Japanese   Publishing type：Rapid communication, short report, research note, etc. (bulletin of university, research institution)  

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Authorship：Lead author   Language：English   Publishing type：Internal/External technical report, pre-print, etc.   Publisher：NTT Review  

The ATM probe is a system intended for measuring traffic and QoS at each of the ATM, IP the TCP/UDP layers. The functions of this probe are realized by software in the PC. The probe has no effect on communication that is actually taking place. It also permits measurement without imposing a load on the network equipment.

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Authorship：Lead author   Language：Japanese   Publishing type：Internal/External technical report, pre-print, etc.  

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Language：Japanese   Publishing type：Internal/External technical report, pre-print, etc.  

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Language：Japanese   Publishing type：Internal/External technical report, pre-print, etc.   Publisher：NTT R and D  

With networks like the Internet becoming increasingly utilized by businesses, network service providers are being asked to guarantee high QoS by making service level agreements with their users. To provide high QoS, they need to be able to measure network conditions in order to manage bandwidth and quality. In this paper, we introduce a monitoring system called "ATM probe", which measures traffic and QoS of IP-over-ATM packets.

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Language：Japanese   Presentation type：Oral presentation (general)  

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