Research

High-performance Transport Protocol
High-bandwidth links ranging from 1 to 10 Gbit/s are increasingly in fashion around the world. Our goal is to develop a high performance transport protocol that can enhance end-to-end performance even in the high bandwidth-delay product networks. To this end, we propose SIRENS, a scalable, robust, and flexible fine-grained explicit notification framework. The key concept of SIRENS is that network information at each hop router (available bandwidth, link bandwidth, queue size, loss rate, etc) is collected with hop-by-hop basis and per-packet frequency by end-hosts and the end-hosts grasp the network condition by interpreting the collected information. This framework supports achievement of very precise and fast-converged congestion control for a broad class of transport protocols.

Peer-to-Peer Network
The technology to distribute identical data simultaneously to multiple hosts is essential for large-scale applications such as file distribution, video distribution, and network collaboration. Although IP multicast, which is achieved in the network layer, is expected for such applications so far, several problems inherent in its original architecture delays the deployment of IP multicast into the Internet. We are now investigating Peer-to-Peer (P2P) multicast architecture achieved in the application layer. In P2P multicast, data are duplicated at hosts and are transmitted to other hosts using multiple unicast connections. Therefore P2P multicast incurs no problem of IP multicast. P2P multicast, however, is subject to partition of the multicast tree caused by host's leave or failure, because the tree is formed by end-hosts only. For the purpose of fast tree rebuilding, we are developing multi-path routing algorithm for P2P multicast.

Video Multicast
Video distribution using multicast communication is bandwidth-efficient scheme and could be major application on the next generation Internet. Video Multicast is required to cope with heterogeneity of the network such as difference of processing power of each receiver and of available bandwidth for each receiver. The attractive solution is layered multicast. We are currently developing "Network-supported Layered Multicast".

Publications

Journal

• N. Mimura, K. Nakauchi, H. Morikawa, and T. Aoyama,
  Functional Unit Oriented Middleware for Application-Level Multicast Services. [ pdf (757KB) ]
  IEICE Transactions on Communications, Vol. E88-B, No. 12, pp. 4442-4450, Dec. 2005.
• K. Nakauchi, Y. Ishikawa, H. Morikawa, and T. Aoyama,
  Exploiting Semantics in Unstructured Peer-to-Peer Networks. [ pdf (1469KB) ]
  IEICE Transactions on Communications, Vol. E87-B, No. 7, pp. 1806-1817, July 2004.
• T. Ha Nguyen, K. Nakauchi, M. Kawada, H. Morikawa, and T. Aoyama,
  Rendezvous Point Based Layered Multicast. [ pdf (397KB) ]
  IEICE Transactions on Communications, Vol. E84-B, No. 12, pp. 3133-3140, Dec. 2001.
• K. Nakauchi, K. Kaneko, A. Saito, and H. Morikawa,
  A Real-time Multimedia Communication System using Digital Video. [ pdf (643KB) ]
  IPSJ Magazine, Vol. 42, No. 8, pp. 793-798, Aug. 2001. (in Japanese)
• K. Nakauchi, H. Morikawa, and T. Aoyama,
  Network-supported Rate Control for Layered Multicast. [ pdf (1161KB) ]
  IEICE Transactions on Communications, Vol. J84-B, No. 3, pp. 365-379, Mar. 2001. (in Japanese)

International Conference

• K. Nakauchi and K. Kobayashi,
  Studying Multi-rate Multicast Congestion Control with Explicit Router Feedback.
  Forth International Workshop on Protocols for Fast Long-Distance Networks (PFLDnet 2006), Nara, Japan, Feb. 2006.
• K. Nakauchi and K. Kobayashi,
  Exploiting Fine-grained Explicit Router Feedback Towards High-performance Transport Protocols.
  The 2006 International Symposium on Applications and the Internet (SAINT 2006), Phoenix, Arizona, USA, Jan. 2006.
• N. Mimura, K. Nakauchi, H. Morikawa, and T. Aoyama,
  A Middleware Approach for Supporting Application-level Multicast Services.
  First International Workshop on Ad Hoc, Sensor and P2P Networks (AHSP 2005), Jiuzhaigou, China, April 2005.
• K. Nakauchi and K. Kobayashi,
  Studying Congestion Control with Explicit Router Feedback Using Hardware-based Network Emulator. [ pdf (291KB) ]
  Third International Workshop on Protocols for Fast Long-Distance Networks (PFLDnet 2005), Lyon, France, Feb. 2005.
• K. Nakauchi, H. Morikawa, and T. Aoyama,
  Design and Implementation of a Semantic Peer-to-Peer Network. [ pdf (753KB) ]
  7th IEEE International Conference on High Speed Networks and Multimedia Communications (HSNMC 2004), Toulouse, France, June 2004.
• K. Nakauchi, H. Morikawa, and T. Aoyama,
  Semantic Peer-to-Peer Search Using Query Expansion.
  The Second Workshop on Semantics in Peer-to-Peer and Grid Computing (SemPGRID 2004), New York, NY, USA, May 2004.
• K. Nakauchi, Y. Ishikawa, H. Morikawa, and T. Aoyama,
  Peer-to-Peer Keyword Search Using Keyword Relationship.
  Third International Workshop on Global and Peer-to-Peer Computing on Large Scale Distributed Systems (GP2PC 2003), Tokyo, Japan, May 2003.
• N. Mimura, K. Nakauchi, H. Morikawa, and T. Aoyama,
  RelayCast: A Middleware for Application-level Multicast Services.
  Third International Workshop on Global and Peer-to-Peer Computing on Large Scale Distributed Systems (GP2PC 2003), Tokyo, Japan, May 2003.
• K. Nakauchi, H. Morikawa, and T. Aoyama,
  A Router Support Framework for Multicast Video Distribution.
  7th Asia Pacific Conference on Communications (APCC 2001), pp. 586-589, Tokyo, Japan, Sept. 2001. (Also in IEICE Transactions on Communications, Vol. E84-B, No. 11 Appendix, pp. 586-589, Nov. 2001.)
• K. Nakauchi, H. Morikawa, and T. Aoyama,
  A Network-Supported Approach to Layered Multicast. [ pdf (330KB) ]
  IEEE International Conference on Communications (ICC 2001), pp. 1227-1231, Helsinki, Finland, June 2001.
• K. Nakauchi, H. Morikawa, and T. Aoyama,
  Network-supported Rate Control Mechanism for Multicast Streaming Media. [ pdf (530KB) ]
  The 2001 Symposium on Applications and the Internet (SAINT-2001), pp. 131-138, San Diego, California, USA, Jan. 2001.
• K. Nakauchi, H. Morikawa, and T. Aoyama,
  Loss-less and Fair Multicast Congestion Control in Heterogeneous Environments.
  6th Asia Pacific Conference on Communications (APCC 2000), pp. 645-649, Seoul, Korea, Oct. 2000.
• Y. Ishikawa, M. Kawada, K. Nakauchi, H. Morikawa, and T. Aoyama,
  Retransmission Flow Control Mechanism for Reliable Multicast using Adaptive Caching.
  6th Asia Pacific Conference on Communications (APCC 2000), pp. 635-639, Seoul, Korea, Oct. 2000.
• T. Ha Nguyen, M. Kawada, K. Nakauchi, H. Morikawa, and T. Aoyama,
  A Congestion Control Method for Layered Multicast in Sparse Mode Routing.
  6th Asia Pacific Conference on Communications (APCC 2000), pp. 640-644, Seoul, Korea, Oct. 2000.
• Y. Tajima, K. Nakauchi, H. Morikawa, and T. Aoyama,
  Active Network Support for Reliable Multicast.
  5th Asia Pacific Conference on Communications (APCC'99), pp. 513-516, Bejing, China, Oct. 1999.
• M. Kawada, K. Nakauchi, H. Morikawa, and T. Aoyama,
  Multiple Streams Controller for Layered Multicast.
  5th Asia Pacific Conference on Communications (APCC'99), pp. 65-68, Bejing, China, Oct. 1999.

Technical Report (partly in Japanese)

• K. Nakauchi and K. Kobayashi,
  An Explicit Notification Scheme for High-performance Transport Protocols.
  IPSJ Symposium on Multimedia, Distributed, Cooperative and Mobile Systems (DICOMO 2005), June 2005.
• K. Nakauchi and K. Kobayashi,
  Unified Explicit Router Feedback Framework for Unicast and Multicast Congestion Control.
  IEICE Technical Report, IN2004-xxx/NS2004-290, Mar. 2005.
• K. Nakauchi, H. Morikawa, and T. Aoyama,
  Design and Implementation of a Semantic Peer-to-Peer Network.
  IEICE Technical Report, IN2003-xxx/NS2003-317, Mar. 2004.
• K. Nakauchi, H. Morikawa, and T. Aoyama,
  Distributed Srorage Services for Relevant Contents.
  IEICE Technical Report, IN2002-242/NS2002-269, Mar. 2003.
• K. Nakauchi, H. Morikawa, and T. Aoyama,
  Distributed Content Location for Ubiquitous Environments.
  IEICE Technical Report, IN2002-xxx/NS2002-110/CS2002-xxx, Sept. 2002.
• N. Mimura, K. Nakauchi, H. Morikawa, and T. Aoyama,
  RelayCast: Middleware for Peer-to-Peer Streaming Distribution.
  IEICE Technical Report, IN2002-42, July 2002.
• T. Oka, K. Nakauchi, M. Minami, H. Morikawa, and T. Aoyama,
  Discovery of Peers with Similar Interests for A Recommender System.
  IPSJ Symposium on Multimedia, Distributed, Cooperative and Mobile Systems (DICOMO 2002), pp. 141-144, June 2001.
• Y. Ishikawa, K. Nakauchi, H. Morikawa, and T. Aoyama,
  A Peer-to-Peer File Locating Mechanism Using Keyword-Relationship.
  IEICE Technical Report, IN2001-232/NS2001-276, Mar. 2002.
• K. Nakauchi, J. Cheng, H. Morikawa, and T. Aoyama,
  Multi-path Routing Algorithm for Peer-to-Peer Multicast.
  IPSJ Symposium on Multimedia, Distributed, Cooperative and Mobile Systems (DICOMO 2001), pp. 319-324, June 2001.
• K. Osaki, M. Kawada, K. Nakauchi, H. Morikawa, and T. Aoyama,
  A Member-Clustering Scheme for Many to Many Multicast.
  IPSJ Technical Report, 2001-DPS-103-18, June 2001.
• K. Nakauchi, H. Morikawa, and T. Aoyama,
  Rate Control Mechanism for Multicast Streaming Media.
  IPSJ Symposium on Multimedia, Distributed, Cooperative and Mobile Systems (DICOMO 2000), pp.421-426, June 2000.
• Y. Ishikawa, M. Kawada, K. Nakauchi, H. Morikawa, and T. Aoyama,
  Retransmission Flow Control Mechanism for Reliable Multicast using Adaptive Caching.
  IEICE Technical Report, IN2000-16, May 2000.
• T. Ha Nguyen, M. Kawada, K. Nakauchi, H. Morikawa, and T. Aoyama,
  A Congestion Control Method for Layered Multicast in Sparse Mode Routing.
  IEICE Technical Report, IN2000-17, May 2000.
• K. Nakauchi, H. Morikawa, and T. Aoyama,
  Network Support Mechanism for Layered Multicast.
  IEICE Technical Report, IN99-172/SSE99-209, Mar. 2000.
• K. Nakauchi, H. Morikawa, and T. Aoyama,
  A Rate Control Scheme for Layered Multicast with Network Support.
  IPSJ Technical Report, 2000-DPS-97-37/2000-CSEC-8-37, Mar. 2000.
• K. Sasaki, K. Nakauchi, H. Morikawa, and T. Aoyama,
  Multicast-oriented Queue Management Algorithm using Priority Drop.
  IPSJ Symposium on Multimedia, Distributed, Cooperative and Mobile Systems (DICOMO'99), pp. 7-12, June 1999.
• M. Kawada, K. Nakauchi, K. Sasaki, H. Morikawa, and T. Aoyama,
  Multiple Streams Controller for Layered Multicast.
  IEICE Technical Report, IN99-16, May 1999.
  (IEICE Information Networks(IN) Technical Group Award)

Biography

Kiyohide Nakauchi received the B.E., M.E., and Ph.D. degrees from Department of Information and Communication Engineering at The University of Tokyo, Tokyo, Japan in 1998, 2000, and 2003 respectively. At the university, he was a member of Aoyama & Morikawa Laboratory. He joined The Communications Research Laboratory (CRL), Tokyo, Japan in 2003. He is currently a researcher of Network Architecture Group, The National Institute of Information and Communications Technology (NICT), Tokyo, Japan. He is a member of IEEE, ACM, IEICE (The Institute of Electronics, Information and Communication Engineers), and IPSJ (Information Processing Society of Japan).

Personal Interest

Photo Album (Japanese only)