End-to-end communications on 10 Gigabit Ethernet (10 GbE) WAN became popular. However, there are difficulties that need to be solved before utilizing Long Fat-pipe Networks (LFNs) by using TCP. We observed that the followings caused performance depression: short-term bursty data transfer, mismatch between TCP and hardware support, and excess CPU load. In this research, we have established systematic methodologies to optimize TCP on LFNs. In order to pinpoint causes of performance depression, we analyzed real networks precisely by using our hardware-based wire-rate analyzer with 100-ns time-resolution. We took the following actions on the basis of the observations: (1) utilizing hardware-based pacing to avoid unnecessary packet losses due to collisions at bottlenecks, (2) modifying TCP to adapt packet coalescing mechanism, (3) modifying programs to reduce memory copies. We have achieved a constant through-put of 9.08 Gbps on a 500 ms RTT network for 5 h. Our approach has overcome the difficulties on single-end 10 GbE LFNs.

As the network speed grows, inter-layer coordination becomes more important. This paper shows 3 inter-layer coordination methods; (1) "Comet-TCP"; cooperation of data-link layer and transport layer using hardware, (2) "Transmission Rate Controlled TCP (TRC-TCP)"; cooperation of data-link layer and transport layer using software, and (3) "Dulling Edges of Cooperative Parallel streams (DECP)"; cooperation of transport layer and application layer. We show the experimental results of file transfer at Bandwidth Challenge in SC2003; one and a half round trip from Japan to U.S., 15,000 miles, which has 350 ms RTT and 8.2 Gbps bandwidth. Comet-TCP hardware solution attained max 7.56 Gbps using a pair of 16 IA servers, which is 92% of available bandwidth and DECP software attained max 7.01 Gbps using a pair of 32 IA servers.

We propose data sharing facility for data intensive scientific research, "Data Reservoir"; which is optimized to transfer huge amount of data files between distant places fully Utilizing multi-gigabit backbone network. In addition, "Data Reservoir" can be used as an ordinary UNIX server in local network without any modification of server softwares. We use low-level protocol and hierarchical striping to realize (1) separation of bulk data transfer and local accesses by cashing, (2) file-system transparency, I.e. interoperable whatever in higher layer than disk driver, including file system. (3) scalability for network and storage. This paper shows our design, implementation using iSCSI protocol [1] and their performances for both 1Gbps model in the real network and 10Gbps model in our laboratory.

Article Free Access Share on Speculative execution model with duplication Authors: Kei Hiraki Department of Information Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 Japan Department of Information Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 JapanView Profile , Junji Tamatsukuri Department of Information Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 Japan Department of Information Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 JapanView Profile , Takashi Matsumoto Department of Information Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 Japan Department of Information Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 JapanView Profile Authors Info & Claims ICS '98: Proceedings of the 12th international conference on SupercomputingJuly 1998 Pages 321–328https://doi.org/10.1145/277830.277907Online:13 July 1998Publication History 5citation337DownloadsMetricsTotal Citations5Total Downloads337Last 12 Months3Last 6 weeks1 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my AlertsNew Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteeReaderPDF