Dynamic Performance Evaluation and Design of Information Highways
Project/Area Number  08680447 
Research Category 
GrantinAid for Scientific Research (C)

Section  一般 
Research Field 
社会システム工学

Research Institution  Hokkaido University 
Principal Investigator 
KIMURA Toshikazu Hokkaido University, Faculty of Economics, Professor, 経済学部, 教授 (50143649)

Project Fiscal Year 
1996 – 1997

Project Status 
Completed(Fiscal Year 1997)

Budget Amount *help 
¥2,500,000 (Direct Cost : ¥2,500,000)
Fiscal Year 1997 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1996 : ¥2,000,000 (Direct Cost : ¥2,000,000)

Keywords  information highways / performance evaluation / networks / queues / stochastic processes / teletraffic / congestion control / 情報ハイウェイ / 性能評価 / ネットワーク / 待ち行列 / 確率過程 / 通信トラヒック / 輻輳制御 
Research Abstract 
This research deals with the design and control of modern information highways. The main purposes are (i) to develop a continuous model as a network design tool, and (ii) to examine the model efficiency in controlling networks. To these purposes, I obtained the following results. 1.Under general assumptions on the arrival and service processes of packets in a network, I obtained a new diffusion model approximating the queuelength process in each node of the network, which is called the BDbased diffusion model. The new model has significant advantage over others on the accuracy, that is, it is consistent with any known exact results, whereas the previous diffusion models are not. Also, the new model can be easily applied to some network design problems such as optimal buffer design, because the approximate queuelength distribution is given in an explicit form. This result is summarized in a paper under submission ; see the data #2 in the report. 2.I applied the BDbased diffusion model to a finitecapacity multiserver queue, obtaining an approximate queuelength distribution that is consistent with the general arrival and exponential service case. This result is summarized in a paper under submission ; see the data #3 in the report. 3.Assuming pseudo local balance in each node and using the BDbased diffusion model, I developed a continuous model for a general closed queueing network. This result have been presented in the 1997 Spring National Meeting of the OR Society of Japan ; see the data #4 in the report. 4.To compare the BDbased diffusion model with the previous ones, I surveyed diffusion models for queues in computer/communication systems. It is found from this survey that the BDbased diffusion model is also useful in the design and control of computer systems such as database management problems. The survey and related results are summarized in two separate papers ; see the data _<5 and >6 in the report.

Report
(4results)
Research Output
(3results)