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A dynamic circuit network (DCN) provides an advance bandwidth reservation (ABR) service across multiple administrative domains. The On-demand Secure Circuits and Advance Reservation System (OSCARS) is a DCN controller deployed in many networks, for example, the Energy Sciences Network (ESnet) and Internet2 in USA, Rede Nacional de Ensino e Pesquisa (RNP) in Brazil, and JGN-X (a new generation network testbed) in Japan. This paper proposes inter-domain QoS scenarios and an extension of a new path computation element (PCE) with Attribute-Mapping for quality of services (QoS) differentiation in OSCARS. Our modified OSCARS performs a QoS mechanism in which network resources are reserved for high priority requests to ensure low request blocking probabilities (RBPs). Our proposal differentiates among requests for both intra- and inter-domain communications.

In recent years, data centers have needed to process large amounts of data because of various growing Internet services. In a data center, it is important to provide high performance and to reduce energy costs. Consequently, optical network technology is a solution for a data center network. In particular, optical circuit switching is considered as a realistic architecture. Helios, which is a data center network architecture with optical circuit switching, considers only rack-to-rack paths. Helios has a problem in that packet losses occur if many connections are sent to one host. In this paper, we propose two path establishment methods that occupy or share one wavelength link with optical circuit switching in a data center network. We also evaluate performance through simulation. As a result, we show that the proposed path establishment method sharing a wavelength link has approximately a 74% higher throughput than Helios.

The Petaflow project aims to contribute to the use of high performance computational resources to the benefit of society. To this goal the emergence of adequate information and communication technologies with respect to high performance computing-networking-visualisation and their mutual awarness is required. The developed technology and algorithms are presented and applied to a real peta-scale data intensive scientific problem with social importance, i.e. human upper airflow modeling.

Recently, the concept of Software-Defined Network (SDN), which allows us to administer and configure a network in a centralized and software-programming manner, has gathered network engineers' and researchers' attention rapidly. In particular, the expectation and concern to OpenFlow as an implementation of the SDN is remarkable. As a result, research activities, which include prototyping, implementation, demonstration and experiments, conducted over OpenFlow networks have been a worldwide tendency. In such research activities, however, the difficulty in understanding network topology, traffic amount and an actual path of a network flow on the OpenFlow network, and the intricacies in debugging software designed for OpenFlow are serious problems in the development process of OpenFlow controller. This research aims to realize a visualization software that facilitates researchers to perform OpenFlow controller development and demonstration experiments performed on an actual OpenFlow network. In this paper, the authors summarize the achievement of their research work in progress as well as the future direction.

Dynamic circuit network (DCN) refers to an on-demand virtual circuit (VC) service in which a user makes a request for a circuit in advance via a Web page. On-demand Secure Circuits and Advance Reservation System (OSCARS) is well-known DCN software. All requests in DCN/OSCARS are guaranteed bandwidth. Therefore, the quality of service (QoS) can be determined by the request blocking probability (RBP). Several QoS provisioning mechanisms, such as the bandwidth allocation policy (BAP) and preemption, have been proposed in the literature in order to ensure low RBPs for high-priority users. This paper proposes the extension of path computation elements (PCEs) in OSCARS version (v.) 6, called the UP-PCE, which considers the user attributes in its computation. Our extended OSCARS with the UP-PCE can determine two mechanisms: the control of the available topology and the BAP.

The deployment of wide-area OpenFlow networks is essential for the global research community. Although OpenFlow's first target was campus network, we cannot ignore its wide-area deployment, especially from the perspective of Future Internet (FI) R&D. In this paper, we propose design and implementation of the “Extended RISE controller”(eRISE). The eRISE is a modified version of RISE controller which is OpenFlow controller for our OpenFlow testbed network “RISE”(Research Infrastructure for large-Scale network Experiments). Also, we discuss “Interdomain” function for OpenFlow testbed. Finally, we discuss about current issues and future works.

In this paper, we describe a new hypertext‐based score system, called Hyperscore. First, we model the spatial musical semantic structure based on a structured hypertext and then build the Hyperscore representation. Hyperscore can present various views of the musical semantic structure. The system has four view‐generation functions: selection of the music structure; projection of the structure to a particular view; emphasized display for easy understanding; and abstraction to control the amount of details displayed. Besides these mechanisms, semistructured information can be represented by means of annotations.

In today's datacenter networks, TCP protocol is still used in most of the network traffic. On the other hand, TCP protocol can also result in severe goodput collapse in a high bandwidth and low latency datacenter environment. One of the problems is called incast problem. In order to efficiently utilize the bandwidth of distributed systems such as datacenter environments, some traffic control mechanisms should be very necessary. In this paper, we discussed about an application layer control mechanism to improve the performance of certain traffic pattern which may cause incast problem. The main idea is to make the data flows be staggered and transferred in serialized manner. We conducted both simulation-based and real-machine-based experiments. We find out that staggered flows are able to avoid incast problem and to make the performance better in most cases.

The approach of deploying hybrid wide-area Open-Flow networks is essentially important for gradual deployment of the OpenFlow technology into existing wide-area networks because it is impractical to replace such wide-area networks with OpenFlow-enabled ones at once. On the other hand, the design, deployment, and operation of such hybrid OpenFlow networks are often conducted intuitively without in-depth technical considerations. In this paper, we discuss systematically the technical and architectural aspects of hybrid OpenFlow networks based on the experiences obtained so far in the development of our wide-area hybrid OpenFlow networks on JGN2plus/JGN-X, which is nation-wide network testbed in Japan. We also describe the design and operation of RISE (Research Infrastructure for large-Scale network Experiments) on JGN-X, whose objective is to support a variety of OpenFlow network experiments.

Dynamic circuit network (DCN) is one of the technologies in the Future Internet and it has been utilized in many world-wide test beds. DCN provides the on-demand virtual circuit (VC) service in which the user gives requirements, including the source, the destination, an amount of bandwidth, and the start and end times, to the DCN system through the Web page and the system automatically sets up and tears down the end-to-end connection according to the user's request. The user is notified of the status of a reservation (accepted or rejected) on his/her Web browser. Instead of sending the rejection notification when there is insufficient bandwidth, our proposed scheduling scheme, called dynamic time scheduling (DTS), displays available transmission periods on the user's Web browser and the user can select one of choices. The performances of DTS are presented by simulation results.

Universities are constantly searching for ways that prepare students as effective global professionals. At the same time, cyber infrastructure leverages computing, information, and communication technology to perform research, often in an international context. In this paper we discuss a novel model, called the Cyber infrastructure Internship Program (CIP), which serves both of these goals. Specifically, students apply or develop cyber infrastructure to solve challenging research problems, but they do this via summer internships abroad. CIP has been implemented at three different Universities: The University of California San Diego in the US, Osaka University in Japan and and Monash University in Australia. We discuss details of the schemes and provide some initial evaluations of their success.

Visualization has been taking a role of much importance in both science and business areas. For scientists, visualization is a method to gain the meaning of and insight from scientific data and computational results; for business marketing area, computer visualization is popular as a digital signage technology. Recently, tiled display wall (TDW) has gathered users' attention and concern as a promising large-scale visualization technique. SAGE (Scalable Adaptive Graphics Environment) is a representative middleware for realizing such a TDW and experimentally used in an inquisitive way at research institutions and universities. However, this SAGE has an undesirable problem that existent X-window based visualization applications are not displayed without source code modification, although it provides a suite of APIs with which developers can write visualization applications displayed on the SAGE-enabled TDW. In this paper, we present an adapter solution that allows users to display X-window application on the SAGE-based TDW without source code modification. In our evaluation, the developed adapter solution incurred a small overhead in displaying an X application onto a SAGE-enabled TDW, in comparison with the case of modifying the source code of it.

Providing large scale, stable and robust computing environments is indispensable to various fields including scientific researches as well as business. Grid computing has gathered considerable attention as a means to efficiently and effectively utilize computational resources among multiple organizations. However, the current Grid technologies do not always provide the computational environment enough to satisfy users' requirements because of the heterogeneity and disconnect among computational resources on the Grid. For the reason, we have been attempting to develop a new middleware that leverages newly emerging Cloud technologies and allows for a virtual cluster composed of virtual computational resources by Xen as a virtualization technology on top of an overlay network realized by PIAX as an overlay networking technology. In this paper, we propose a system that allows Xen-based virtual computational resources composing a virtual cluster to communicate with each other toward the future development of Grid and Cloud middleware technology. The evaluation shown in the paper indicates that such a virtual cluster is feasible and could work effectively for computationally intensive applications.

In this work, we implemented a messaging system called MONAC, by which users can disseminate Twitter messages via smartphone-based DTN. MONAC is implemented on an overlay network middleware called PIAX. We extended PIAX to enable DTN with dynamic selection of available underlay network and seamless authentication for SNS account of cloud. By these mechanisms, messages can be disseminated via DTN on heterogeneous underlay networks without falsification and user ID frauds.

This paper discusses vision and challenges toward realization of {\em peta-flow computing}, which enables peta-scale information processing and communication. A promising application for peta-flow computing, a large-scale upper airway flow simulation and visualization over a long-fat network, is discussed with its requirements on peta-flow computing. Also, challenges and implications of three technological fields of peta-flow computing -- {\em peta-scale computing}, {\em peta-scale networking}, and {\em peta-scale interfacing} are identified.

In the Skip Graph, which is a structured overlay network that supports range retrievals, a key is supposed to consist of a single value. Therefore, the Skip Graph cannot perform range-to-range retrievals. In the present research, we extend the Skip Graph, enabling it to retain a range as a key, and propose the Range-Key Skip Graph, which can perform range-to-range retrievals. We also implement the proposed scheme and evaluate it on the PlanetLab.

WiFi Positioning System (WPS) plays important role in Ubiquitous applications. It shows shorter response time than GPS and provides more precise position than Cell towers. It is widely used in hybrid positioning systems, e.g. GPS and WPS. The main problem of WPS is how to collect WiFi Access Point (AP) positions because the most of AP positions are not published. So thus, WPS providers collect AP positions by themselves or rely on the WPS user's report. There are several WPS provided, some are commercial system and the others are voluntarily provided. Outdoor position estimation method are already established in commercial system, however, the indoor case requires some more researches. It is necessary to keep voluntarily WPSs. In this paper, we propose an open method to select precise position reported by users to keep WPS estimation accuracy. The proposed method is basically based on the precision preservation methods used in GPS. WPS does not have the same degree of accuracy as GPS, it should be verified the effectiveness in WPS. We have some consideration about the applicability of the proposed method.

International audience; The Petaflow project aims to contribute to the use of high performance computational resources to the benefit of society. To this goal the emergence of adequate information and communication technologies with respect to high performance computing-networking-visualisation and their mutual awareness is required. The developed technology and algorithms will be applied to a real peta-scale data intensive scientific problem with social importance, i.e. human upper airway flow modelling.

This chapter describes a wireless sensor network testbed, named XSensor, that integrates multiple sensor networks. X-Sensor manages multiple wireless sensor networks constructed at different sites, which can be accessed by remote users. This makes easy for users to conduct experiments in different environments. Moreover, X-Sensor provides real sensor data acquired by sensor nodes in each sensor network, which are useful for researchers working on research fields related to sensor data such as sensor data mining and analysis.

The computational speech science portal is a highly intensive data sharing and remote visualization environment that uses e-Science technologies to support scientists in accessing distributed databases and visualization resources for solutions of the physics of human speech problems. These recourses include input files specifying the human oral cavity geometry of speech, and proprietary software and hardware for visualization and data sharing of computational fluid dynamics (CFD) results. Through a Web-based grid portal, a user can access these resources and collaboratively visualize the results of the CFD simulation and sharing the result of it. Thus, the portal allows users to use the e-science infrastructure to share resources among geographically distributed partners in order to execute large-scale CFD simulations and to collaboratively analyze and visualize the results. However, among geographically distributed partners, large-scale data normally cannot be transferred in a short period of time because of the long round-trip time of the TCP protocol. This chapter describes the web-based portal, built on the Gridsphere framework. The portal is composed of a number of JSR-168 compliant portlets that deploy services at the back end for the management of distributed resources and for the invocation of services for visualization. The chapter also describes how high-speed data transfer is achieved through the e-science infrastructure.

An overlay network called Range-key Skip Graph (RKSG) has been proposed that can perform range-to-range search on peer-to-peer network. In this paper, we propose a large scale key-value store realized on RKSG, which is possible to scale-out a database with range query. Moreover, applications that utilize the store are implemented and will be demonstrated through private PlanetLab on JGN2plus.

M. Sekido∗,a N. Kawaguchi,b Y. Koyama,c M. Kimura,a T. Kondo,cd H. Takiguchi,a T. Hobiger,c K. Takefuji,a H. Harai,c T. Ikeda,c S. Shimojo,c T. Oyama,b T. Hara,b Y. Kono,b S. Kurihara,e K. Kokado,e D. Tanimoto,e K. Nozawa,e H. Takeuchi, f H. Uose,g K. Fujisawa,h H. Takabai a Kashima Space Research Center, National Institute of Information and Communications Technology, 893-1 Hirai Kashima Ibaraki, 314-8501, Japan, E-mail: sekido@nict.go.jp b National Astronomical Observatory, 2-21-1 Osawa, Mitaka, Tokyo, 181-8588, Japan ,kawagu.nori@nao.ac.jp c Next Generation Network Research Center, National Institute of Information and Communications Technology, 4-2-1, Nukui-Kitamachi, Koganei, Tokyo 184-8795, Japan d Ajou University, Paldai Hall 901, Worcheon-Dong, Yeongtong-Gu, Suwon 442-749, Korea e Geographical Survey Institute, 1Kitasato, Tsukuba 305-0811, Japan f Japan Aerospace Exploration Agency/Institute of Space and Astronautical Science, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510, Japan g Nippon Telegraph and Telephone Corporation, Musashino Research and Development Center, 3-9-11 Midori-cho, Musashino-shi, Tokyo, 180-8585, Japan h Yamaguchi University, 1677-1 Yoshida, Yamaguchi, Yamaguchi, 753-8511, Japan i Gufu University, 1-1 Yanagito, Gifu, Gifu, 501-1193, Japan

The recent rapid developments in network technologies have made the use of high-speed networks possible. This has enabled e-Science environment to be established on a global scale. To share and transfer the voluminous amount of data available in e-Science, high-speed transport protocols that efficiently use bandwidth have been extensively studied. However, when many high-speed transport protocols coexist on a bottleneck link, they often cannot effectively recognize congestion conditions. So that, an extraordinary traffic stream occupies bandwidth, and transfer speec of other traffic streams goes down. We address this problem by proposing a buffer control method that mitigates the effects of contention between high-speed transport protocols. It estimates inflow rates and controls outfloww rates at a router, and drops packets in accordance with a discarding probability value before the buffer becomes full. Simulation results confirm that our method works well functionally.

We have been studying a service coordination technology that enables users to use the various types of service elements that are available in a ubiquitous computing and networking environment. We have adopted a user context handling mechanism to choose suitable service components. In this paper, we proposed an adaptive information delivery method for personalized recommendation and information provisioning. This method can provide information services based on user location, preferences, or moving history to everyone, everywhere, using a mobile phone. This system is an information circulation system based on social capital, which refers to connections between social networks. Users can obtain information about events, sightseeing information, gourmet information, disaster prevention information from SNS by marking the location information. We also applied a location-dependent recommendation method based on user's movement history. We conducted a field trial to evaluate feasibility of the system. According to the results of our questionnaire, the information-provision style is acceptable to the users. In addition, according to the analysis of the user movement and user preferences, there was a correlation between user's visited place and interested genres.

Recently, environment monitoring system attracts attention because global and/or local disasters such as global warming problem, air pollution, heavy rain and flood etc. occur everywhere. In addition, some people and companies have a weather sensor and broad band internet service become widespread as weather sensor and internet service cost lower. Many of these existing sensor network are operated by Server-Client model. However, it is difficult to manage a number of distributed sensors, and this model is weak for fault tolerance. We adopt P2P model in order to correct the necessary information effectively. On the other hand, the number of weather sensors cannot be satisfied enough to cover an arbitrary point on the earth though the users of such a weather sensor network are keen to know the information around them. In this paper, we present the method of spatial interpolation of the weather sensor data on P2P network based on location information.

This paper introduces a new sensor network testbed, X-Sensor, that integrates multiple sensor networks deployed at different sites. X-Sensor provides three functionalities: (a) a sensor network search which enables users to find a sensor networks appropriate for experiment and data acquisition, (b) a sensor data archive which provides users with various sensor data acquired by sensor nodes, and (c) an experimental testbed which enables remote users to evaluate their network and data management protocols.

This paper introduces a sensor network testbed, X-Sensor, that integrates multiple sensor networks deployed at different sites. X-Sensor provides three functionalities: (a) a sensor network search which enables users to find a sensor networks appropriate for experiment and data acquisition, (b) a sensor data archive which provides users with various sensor data acquired by sensor nodes, and (c) an experimental testbed which enables remote users to evaluate their proposed methodologies.

Future Internet is a clean-slate research activity in the quest of new networking technologies to overcome the limits of the current Internet. In its experimental research, virtualization and federation are emerging as essential features, especially in the construction and operation of the testbeds. Moreover, they are believed to sustain as the fundamental features of the Future Internet itself. Visions and experiences on virtualization and federation are given by leading experts from US, EU, and Asia.

In 2005, Osaka University, in Japan, started an international educational program called, Pacific Rim International University (PRIUS), on top of the Pacific Rim Application and Grid Middleware Assembly (PRAGMA) research framework. The PRIUS framework is based on and similar to that of the PRIME program at the University of California San Diego. Through the PRIUS program, Osaka University has explored a new structure of higher education for graduate students by combining lectures given by PRAGMA researchers and scientists as well as internship abroad opportunities to PRAGMA member institutions and universities. In this paper, we describe the goals and framework of the PRIUS program and discuss issues for the improvement of PRIUS. We also present two examples of interns' achievements as well as other educational effects brought through collaboration with PRAGMA.

In the Cybermedia Center, Osaka University (CMC), we have applied the NAREGI grid middleware to our latest large-scale computing system for nationwide joint-use, and have made grid computing technology available on them coexisting with the conventional computing style. In this paper, we mention the problems of resource provisioning, password/passphrase management, issuance of grid certificate and grid operations in user management, and a solution is discussed.

Recently, Grid computing has gathered the attention as a means to efficiently and effectively utilize computational resources among multiple organizations. However, the current Grid technologies do not always provide the computational environment enough to satisfy users' requirements because of the heterogeneity and disconnect among computational resources on the Grid. For the reason, we have been attempting to develop a new Grid middleware technology that allows for a virtual cluster composed of virtual computational resources by Xen as a virtualization technology on top of an overlay network realized by PIAX as an overlay networking technology. In this paper, we propose a communication relay mechanism that allows Xen-based virtual computational resources composing a virtual cluster to communicate with each other toward the future development of such a Grid middleware technology. The evaluation shown in the paper indicates that such a virtual cluster is feasible and could work effectively for computationally-intensive applications.

In the Cybermedia Center, Osaka University (CMC), we have applied the NAREGI grid middleware to our latest large-scale computing system for nationwide joint-use, and have made grid computing technology available on them coexisting with the conventional computing style. In this paper, we will describe an authentication system solving the problems which we have encountered in construction of the grid environment.

Applications, such as grid computing, process their data over wide-area networks. The schedule of these applications is influenced by the duration of data transfer. Guaranteeing the performance of data transfer is helpful to optimize the schedule of these applications. Diffserv AF is an efficient QoS control method to guarantee the duration of data transfer, but the resource is limited in many network environments. Conventional data transfer methods require much greater network resource than the target rate of data transfer, or it is hard to implement their algorithms into applications. We propose a data transfer middleware that is easy to use and improve the utilization of network bandwidth using plugin for Linux kernel. We evaluate the performance of the algorithm of our middleware with simulation. The algorithm of our middleware requires much smaller network bandwidth to guarantee the duration of data transfer.

We have developed a data transfer method that uses less reserved bandwidth on DiffServ AF networks. Our method consists of a dynamic QoS control method and a data transfer protocol that uses two kinds of TCP connections. We simulated the transfer of data using our method on a network simulator and found that it performed better than current methods. By reducing reserved bandwidth, our method will reduce the cost to network providers of meeting service level agreements with customers. It will be particularly useful in such applications as pipeline processing in large-scale grid computing and remote data backup over wide area networks because these applications will need to reserve less bandwidth than they currently need to meet job schedules.

To use multiprocessor systems efficiently, several load balancing algorithms have been adopted widely. However, most of the algorithms proposed so far can be applied to FCFS systems, and only a few can be applied to time-sharing systems in wide use today. This paper proposes a load balancing algorithm designed to reduce the average response time of processes, introducing a load measure which takes into account the distribution of the work demand of each kind of process. This algorithm can be applied to a multiprocessor system with round-robin scheduling discipline. This algorithm also seems easy to implement on actual systems because load balancing is made by assigning new processes to the lightest loaded processor rather than migrating running processes. According to the simulation experiment, the algorithm proposed here improves the average response time compared with that of the “Join the Shortest Queue” algorithm over all situations investigated.

Applications, such as grid computing, remote backup, and contents distribution, transfer bulk data over wide-area networks. These applications schedule work to satisfy the user requirements. Guaranteeing the performance of data transfer is helpful for scheduling these applications. Diffserv AF is a QoS control method that guarantees data transfer performance. However, the throughput of conventional TCPs is much lower than the reserved bandwidth in congested Diffserv AF networks. Some high-speed protocols reduce the difference between the reserved bandwidth and the average throughput. However, other traffic in the networks influences the throughput of these high-speed protocols. The insufficient throughput stability exists when the background traffic throughput frequently changes in congested networks. Our purpose is to improve the network bandwidth utilization and to make it possible to reserve more bandwidth in Diffserv AF networks. We propose a data transfer method that uses two kinds of TCP flows. One TCP flow reserves network bandwidth and controls the window size to reduce the difference between the throughput and the reservation bandwidth. The other TCP flow transfers data without bandwidth reservation and flow control. This method allows for a higher throughput when the network is uncongested and reduces the difference between the reserved bandwidth and the throughput in congested networks.

Recently, the amount of scientific data has been increasing because of technological advancement in measurement and high-performance computing. As the result, visualization technologies are becoming increasingly important to analyze the scientific data. Among visualization technologies, SAGE is gathering attention of scientists in these days. It not only enables the visualization of tens of million pixel-class high-resolution image but also has the potential to realize the collaboration environment where scientists can work together for their common research purpose. However, there remain still technical issues in SAGE, since it is still in the process of development. A problem of application operability, which prevents SAGE users from efficiently operating various applications on SAGE, is targeted in this paper. This problem is caused from the architectural design that SAGE users have to manage window-related operation and application-related operation from different interfaces. For solving the problem, we have developed a built-in application control module for SAGE. Our built-in application control module unifies the separate interfaces for window management and application operation. As a result, users can control application from a unified user interface, SAGE UI.

The maturity and stability of WSRF and its related technologies is producing a new demand for meta-scheduling WSRF-based services. In fact, many scientific institutions and universities are looking into the possibility of using WSRF-based services as production-level services. For this purpose, they need a meta-scheduling solution that selects one of the WSRF-based services, each of which is deployed in an organization for fault tolerance and load balancing. However, methods for meta-scheduling services among multiple sites have not been discussed well. This paper describes a new framework (MSSA: Meta-Scheduling Service Architecture) for scheduling and selecting WSRF-based services deployed over multiple sites. This framework provides a transparent scheduling method to users. Our method takes advantage of the factory pattern used typical WSRF services. The framework builds scheduling processes into the factory pattern and hides the complexity of the scheduling process from users. MSSA defines a meta-factory service that selects a suitable factory service and delegates the user's request to the factory service. By using this meta-factory service instead of using the original factory services, users can utilize meta-scheduling features transparently. MSSA can build hierarchical structures of meta-factory services to construct scalable scheduling environment, and can also switch scheduling policies easily. In this paper, the design and implementation of MSSA is discussed.

Almost all companies are now utilizing computer networks to support a speedier and more effective in-house information-sharing and communication. However, existing systems are unable to support to enhance communications between users. Therefore, in our research, we implemented an in-house communication support system that integrates the "information propagation model" and "discussion forums." The former is proposed to realize word-of-mouth communication in a social network, while the latter is where users are allocated and discussions are carried out. By applying the system in a real company, we found our system has an effect to enhance communication in the real world and human relations.