Grant-in-Aid for Scientific Research (B)
|Allocation Type||Single-year Grants|
|Research Institution||Kyoto University|
TAKAHASHI Yutaka Kyoto Univ., Grad.School of Informatics, Professor, 情報学研究科, 教授 (00135526)
KAWANO Hiroyuki Nanzan Univ., Fac.of Math. & Inf.Sci., Professor, 数理情報学部, 教授 (70224813)
KAWAHARA Minoru Ehime Univ., Center for Inf.Tech., Associate Professor, 総合情報メディアセンター, 助教授 (50224829)
KASAHARA Shoji Kyoto Univ., Grad.School of Informatics, Assoc.Professor, 情報学研究科, 助教授 (20263139)
MASUYAMA Hiroyuki Kyoto Univ., Grad.School of Informatics, Assis.Professor, 情報学研究科, 助手 (60378833)
|Project Period (FY)
2002 – 2005
Completed(Fiscal Year 2005)
|Budget Amount *help
¥14,700,000 (Direct Cost : ¥14,700,000)
Fiscal Year 2005 : ¥1,400,000 (Direct Cost : ¥1,400,000)
Fiscal Year 2004 : ¥3,000,000 (Direct Cost : ¥3,000,000)
Fiscal Year 2003 : ¥4,700,000 (Direct Cost : ¥4,700,000)
Fiscal Year 2002 : ¥5,600,000 (Direct Cost : ¥5,600,000)
|Keywords||content distribution / QoS / loss probability / transmission delay / realtime / traffic analysis / performance analysis / the Internet / ストリーミング / ARQ / FEC / P2P / 自己組織化アルゴリズム / 実時間トラヒック / 動画像 / モデル化|
We have carried out our research actively towards developing a highly efficient content delivery network from theoretical point of view. Some of our achievements are listed below.
・We have investigated the impact of long-range dependence arising in traffic on the performance of real-time content delivery.
・We have proposed a channel allocation algorithm for a cellular network which allocates channel bandwidth efficiently giving higher priority to voice calls and derived performance measures such as packet loss probability, transmission delay and call loss probability.
・We have developed a mathematical model called a 'polling model' to evaluate the performance of Bluetooth technology for the last hop of content delivery and analytically derived the transmission delay and throughput of the model.
・We have analyzed the performance of some variants of FEC which are based on XOR and clarified the relationship among 1)the number of symbols taken together in a XOR operation, 2)its probability distribution if it is random, 3)the ratio of redundancy to the original data set, 4)the channel error rate 5)the successful transmission probability.
・We have considered the performance of a hybrid FEC/ARQ for the recovery from packet losses and bit errors in real-time content distribution.
・We have proposed an autonomous self-organization algorithm for distributed content delivery systems using overlay networks and demonstrated its usefulness.
・We have developed a mathematical model and its performance analysis for the appropriate design and dimensioning of playout delay and buffer size taking network delay caused by congestion into consideration.
・We have developed a fundamental technique to estimate the traffic volume and distributions of hop counts and round trip time between peers in overlay networks and carried out experimental tests in real networks.