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Digging Deep into the Data Mine with DataMiningGrid

As modern data mining applications increase in complexity, so too do their demands for resources. Grid computing is one of several emerging networked computing paradigms promising to meet the requirements of heterogeneous, large-scale, and distributed data mining applications. Despite this promise, there are still too many issues to be resolved before grid technology is commonly applied to large-scale data mining tasks. To address some of these issues, the authors developed the DataMiningGrid system. It integrates a diverse set of programs and application scenarios within a single framework, and features scalability, flexible extensibility, sophisticated support for relevant standards and different users.

Application of decision trees to smart homes

This chapter aims to illustrate a possible way of using decision trees to make Smart Homes smarter. Decision trees are popular modelling technique, and the corresponding models are both predictive and descriptive. We formulate the modelling problem by defining the generic question “Is the undergoing activity or event in the Smart Home usual?” Then we explain how it is possible to gather appropriate data from the sensors and pre-process these data to form appropriate input for a decision tree algorithm. We further explain the mainstream approaches in decision trees algorithms rather then analysing them in detail, and we give short overview of available software. Finally, we explain some measures for quantitative and qualitative evaluation of the induced decision tree models (e.g. expert opinion, cross-validation, statistical tests etc.).

Improving the performance of Federated Digital Library services

The number of Digital Libraries (DLs) accessible over the Open Archives Initiative-Protocol for Metadata Harvesting (OAI-PMH) has been constantly increasing in the past years. Earlier efforts in the DL area have concentrated on metadata harvesting and provisioning of value-added Federated Digital Library (FDL) services to the users. FDL services, however, have to meet significant performance and scalability requirements, which is difficult to achieve in centralized metadata harvesting systems. The goal of the present study was to evaluate the benefits of using Web Services Resource Framework (WSRF) compliant grid middleware infrastructure for providing efficient and reliable FDL services. The presented FDL application allows for parallel harvesting of OAI-PMH compliant DLs. The results show that this approach efficiently solves the performance related problems, while it also contributes to greater flexibility of the system. The quality of service is improved as metadata can be updated frequently, and the system does not exhibit a single point of failure.

VICTORY: a 3D search engine over P2P and wireless P2P networks

Our information society is being overflowed with digital data of various kinds. In order for the users to find relevant information, novel digital repositories should provide search mechanisms that are both content and context based, facilitating the formulation of queries and enabling search by example using 3D/2D objects, sketches, etc. At the same time the repositories should scale to the growing number of users. This paper presents the main achievements of the IST project VICTORY that aims at developing an innovative distributed digital repository introducing novel search, retrieval, and visualization capabilities to a desktop and mobile P2P networks.

Dynamically reconfigurable workflows for time-critical applications

Cloud-based applications that depend on time-critical data processing or network throughput require the capability of reconfiguring their infrastructure on demand as and when conditions change. Although the ability to apply quality of service constraints on the current Cloud offering is limited, there are ongoing efforts to change this. One such effort is the European funded SWITCH project that aims to provide a programming model and toolkit to help programmers specify quality of service and quality of experience metrics of their distributed application and to provide the means to specify the reconfiguration actions which can be taken to maintain these requirements. In this paper, we present an approach to application reconfiguration by applying a workflow methodology to implement a prototype involving multiple reconfiguration scenarios of a distributed real-time social media analysis application, called Sentinel. We show that by using a lightweight RPC-based workflow approach, we can monitor a live application in real time and spawn dependency-based workflows to reconfigure the underlying Docker containers that implement the distributed components of the application. We propose to use this prototype as the basis for part of the SWITCH workbench, which will support more advanced programmable infrastructures.

QoS-Aware Orchestration of Network Intensive Software Utilities within Software Defined Data Centres: An Architecture and Implementation of a Global Cluster Manager

Although the cloud computing domain is progressing rapidly, the deployment of various network intensive software utilities in the cloud is still a challenging task. The Quality of Service (QoS) for various gaming, simulations, videoconferencing, video streaming or even file uploading tasks may be significantly affected by the quality and geolocation of the selected underlying computing resources, which are available only when the specific functionality is required. This study presents a new architecture for geographic orchestration of network intensive software components which is designed for high QoS. Key elements of this architecture are a Global Cluster Manager operating within Software-Defined Data Centres (SDDCs), a runtime QoS Monitoring System, and a QoS Modeller and Decision Maker for automated orchestration of software utilities. The implemented system automatically selects the best geographically available computing resource within the SDDC according to the developed QoS model of the software component. This architecture is event-driven as the services are deployed and destroyed in real-time for every usage event. The utility of the implemented orchestration technology is verified qualitatively and in relation to the potential gains of selected QoS metrics by using two network intensive software utilities implemented as containers: an HTTP(S) File Upload service and a Jitsi Meet videoconferencing service. The study shows potential for QoS improvements in comparison to existing orchestration systems.

SWITCH-ing from Multi-Tenant to Event-Driven Videoconferencing Services

Full mesh is the most commonly used networking topology in Web Real-Time Communication (WebRTC) based videoconferencing (VC) applications, however, due to its inherently poor scaling capability it is not appropriate for multi-party VC with many participants. Solutions based on centralized media server infrastructures are used to leverage the scaling problem. Service providers adopting centralized approach need to ensure good resource utilization to lower the price, and at the same time provide good Quality of Experience (QoE) to the end users. In practice, even with todays advanced cloud technologies, these two conflicting goals are difficult to achieve simultaneously. In order to tackle this complex problem, we propose an innovative event-driven model, that differs from the traditional multi-tenant service provisioning model. In this work, the architecture and implementation of a WebRTC event-driven multi-party VC, based on Software as a Service (SaaS) principles is presented. A prototype was developed on top of Docker containers and Kubernetes container orchestration technologies, which in our opinion represent key enabling technologies fostering the migration from multi-tenant towards event-driven architectures. The technology readiness to support such time-critical applications is evaluated. The initial results suggest that although there are some trade-offs in terms of performance/resource consumption, our fully functional prototype allows for on-the-fly media server instance creation and destruction in arbitrary cloud provider infrastructure with still acceptable application usability.

Search and retrieval of multimedia objects over a distributed P2P network for mobile devices

Search for and delivery of multimedia content will be of great importance in the years to come. Common data formats and appropriate architectures that will pave the way toward this challenging task must be defined. In this article a framework enabling mobile device users to search for and retrieve multimedia objects over a distributed P2P-based network is presented. The framework was an outcome of the research that took place within the VICTORY European project. The proposed concept is to develop a P2P-based application that, having as a basis the state of the art in the field of 3D search algorithms, would be able to deliver search and retrieval functionalities to users on the move through mobile devices. Following a service-oriented approach, a framework able to deliver these functionalities to mobile user agents in a device- and application-independent way has been implemented.

Information Modelling and Semantic Linking for a Software Workbench for Interactive, Time Critical and Self-Adaptive Cloud Applications

Cloud environments can provide elastic, controllable on-demand services for supporting complex distributed applications. However the engineering methods and software tools used for developing, deploying and executing classical time-critical applications do not, as yet, account for the programmability and controllability that can be provided by clouds, and so time-critical applications do not yet benefit from the full potential of virtualisation technologies. A software workbench for developing, deploying and controlling time-critical applications in cloud environments can address this, but needs to be able to interoperate with existing cloud standards and services in a fashion that can still adapt to the continuing evolution of the field. Semantic linking can enhance interoperability by creating mappings between different vocabularies and specifications, allowing different technologies to be plugged together, which can then be used to buld such a workbench in a flexible manner. A semantic linking framework is presented that uses a multiple-viewpoint model of a cloud application workbench as a means to relate different cloud and quality of service standards in order to aid the development of time-critical applications. The foundations of such a model, developed as part of the H2020 project SWITCH, are also presented.