Yoji Yamato

A service-composition and service-emergence framework for ubiquitous-computing environments

While new network technologies bring ubiquitous-computing environments ever closer, methods to provide suitable services within such environments remain immature. We describe the ubiquitous service-oriented network (USON) architecture, a new service-provision architecture, covering the basic concept, components and their roles, and the service-provision mechanism. A USON provides services in two phases, a service-composition phase in which service elements (SEs) are combined on the basis of service templates (STs), and a service-emergence phase in which a new ST is obtained on the basis of the history of usage of SEs and STs. A USON can handle various types of SEs, representing Web services, computer resources, and sensor devices. The establishment of USON technologies on networks provides various services within ubiquitous-computing environments.

Service Delivery Platform for Telecom-Enterprise-Internet Combined Services

In this paper, we discuss the requirements of a service delivery platform (SDP) and present our SDP. An SDP is an overlay platform that provides interfaces that enable third-party application developers to easily create various applications for the next-generation network (NGN). However, SDP is now just a concept and many vendors and network carriers have proposed different systems for SDP. We evaluated the basic functions of our SDP and confirmed its feasibility.

Method of creating web services from web applications

Web 2.0 is becoming popular among people who are interested in creating or providing more useful services on the Internet. Mashup is one of the most important methods in Web 2.0, which creates services by combining components on the Internet, such as Web services. Mashup enables many people to create various services easily and use services created by many other people. To create such a variety of useful services, we need a large number of components, but there are not so many components available on the Internet yet. We describe an effective method of creating wrappers that make Web applications usable as Web services. The method extracts important segments, such as search results of a hotel search application, from an HTML document generated by the web application and generates extraction rules for the wrappers. This extraction is performed by using the characteristic depth of each tag in the HTML document.

Context-Aware Ubiquitous Service Composition Technology

A context-aware ubiquitous service composition technology is proposed. This can be used in both enterprise and consumer communication service environments. Because the context-awareness is the one of the most important factors in ubiquitous computing, it is insufficient in conventional service integration based on rigid interface design. The flexible service composition based on user context is required. Our proposed approach is that a service composition engine discovers suitable service elements from the network based on the user context and binds them dynamically in accordance with a semantic-level service scenario. Evaluation results show effectiveness and sufficient performance of this architecture.

Fast and Reliable Restoration Method of Virtual Resources on OpenStack

We propose a fast and reliable restoration method of virtual resources on OpenStack when physical servers or virtual machines are down. Many providers have recently started cloud services, and the use of OpenStack, which is open source IaaS software, is increasing. When physical servers are down, there is a fail-over method using the high-availability cluster software such as Pacemaker to restore virtual resources. However, it takes a long time to restore all virtual resources. There is also a method for monitoring each virtual machine by using Ping or other methods and restoring a virtual machine when it is down. However, data may be destroyed due to the double mounts of virtual machines depending on the timing of failures because restoration methods of failed physical servers and virtual machines are independent. Therefore, we propose a fast and reliable restoration method with a uniform way for plural types virtual resources. In our method, Pacemaker only detects a physical server failure and notifies a failure to a virtual resource arrangement scheduler, then a virtual resource arrangement scheduler determines multiple physical servers to restore virtual resources and calls OpenStack APIs to rebuild. The virtual resource arrangement scheduler also detects virtual machine failures by using a Libvirt monitoring module and restores virtual machines without data loss by handling Pacemaker and Libvirt notifications uniformly. We implemented the proposed method and showed its effectiveness regarding fast restoration through performance measurements.

Context-Aware Service Composition and Component Change-over using Semantic Web Techniques

This paper shows the effectiveness of dynamic over of service components for ubiquitous service composition. Although context-aware services are expected in the forthcoming ubiquitous computing era, conventional service coordination techniques are insufficient because of rigid interface designing. To cope with this problem, we have established a flexible service composition framework, where a semantic-level service scenario is translated and its components are dynamically found, selected, and bound. User situations change with time, so service components should be changed in accordance with context change. We propose a new method that reselects and rebinds service components based on context change. Through a performance measurement, we show the effectiveness and practicality of the new method.

Study of Service Processing Agent for Context-Aware Service Coordination

We proposed service processing agent which enables end-users to use context aware services easily. In ubiquitous network environments in the future, context-aware services are expected because the context-awareness is one of the most important factors in ubiquitous network. Therefore, the flexible service composition based on user context is required. Our proposed approach is that a service processing agent searches and selects suitable service components based on the user context and binds them dynamically. Users can send a request to the service processing agent in usual Web service messaging. Through the study, implementation and performance measurement, we showed the effectiveness and practicality of our proposed method.

Development of Service Control Server for Web-Telecom Coordination Service

We propose the Service Control Technology for the Web-telecom coordination service, and we show our proposal effectiveness. In the NGN (Next-Generation Network), many new applications are expected using open network interfaces. In particular, we study the SDP (Service Delivery Platform) for coordinating existing Internet services and telecom services. In this paper, we propose the Service control technology, which handles common process required in the telecom trigger Web-telecom coordination service. Our method achieves improvement in usability of telecom user, reliability of the coordination service, and processing performance. We implement our method two types (Proxy type, Callable type) and measured processing performance. In comparison to related technologies, we show our method effectiveness.

Service composition architecture for programmability and flexibility in ubiquitous communication networks

This paper addresses a new service composition method suitable for the forthcoming ubiquitous computing era. The latest developments in network computer technology have made various entities connected to the Internet, such as Web services, sensors, and home information appliances, accessible to those who want to create their own service capabilities. The architecture we have thus far proposed is a key to achieving the ubiquitous concept, but approaches that spread the use of the architecture are required. We establish the architecture more widely usable in mobile Internet environments and suggest applicable domains for two types of proxy servers to compensate for the shortage of mobile terminal capacities. Practical service examples and business models are also discussed

Context-aware content-provision service for shopping malls based on ubiquitous service-oriented network framework and authentication and access control agent framework

As emerging technologies are being developed, ubiquitous computing environments will be established in the near future. Research on user service provisions over ubiquitous computing environments has been started. The implementation method of an actual service, based on our proposed service-provision framework, is described in this demonstration and we will show the actual implementation in a demonstration area. This is a context-aware contentprovision service, and the content is assumed to be commercial advertisements in a shopping mall. The users can enjoy many types of the content-provision services based on their own profiles, which are used by the authentication and access control agents.