Reference architecture for Virtual Organization

"United we stand, divided we fall" ist eine bekannte Englische Redewendung. Wir leben in der Zeit der virtuellen Zusammenarbeit. Quellen sind logisch und Lösungen virtuell. Fortschritte auf der konzeptionellen und technologischen Ebene verbessern die Weise der menschlichen Kommunikation. Everything-as-a-Service war einmal nur ein Traum. Heute wird es Realität. Auch die Art der zu bewältigenden Probleme hat sich im Laufe der Zeit verändert. Heutzutage wird die Online-Kollaboration Über das Internet (e-Collaboration) in allen möglichen wissenschaftlichen Gebieten angewendet. Medizin, Technik, Meteorologie, Biologie, Chemie, Physik, Erdbeben und Wettervorhersage, Soziale Netzwerke usw., alle benutzen elektronische Plattformen. Umfangreiche Daten und Rechenressourcen sind nötig und auch die Assistenz durch menschlichee Experten wird immer bedeutsamer. Diese Situation stellt eine grosse Verantwortung fÜr IT Forscher und Entwickler dar, generische Plattformen zu schaffen, auf denen Benutzer einfach kommunizieren und Probleme gemeinsam lösen können. Das Verteiltes Rechnen (Distributed Computing) bietet viele technische Paradigmen an, wie zum Beispiel Cluster Computing, Grid Computing, Cloud Computing, um dieses Konzept umzusetzen. Konzeptuell erlauben Virtuelle Organisationen (Virtual Organization) ein harmonisches Zusammenspiel von global verbreiteten Ressourcen, um gemeinsam Ziele zu erreichen. Bestehende Paradigmen und Technologie werden heute in der Praxis zum Aufbau von Virtuellen Organisationen verwendet. Der Mangel an existierenden und anerkannten Standards dazu stellt jedoch ein kritischer Punkt fÜr die letzten zwei Dekaden dar. Unsere ForschungsbemÜhung konzentriert sich daher auf die Entwicklung eines Standards zum Entwurf und zur Realisierung Virtueller Organisationen. Der vorgelegte Standardisierungsansatz besteht aus zwei Phasen. Die erste Phase fÜhrt eine Anforderungsanalyse durch und die zweite Phase stellt eine Referenzarchitektur (Reference Architecture) fÜr Virtuelle Organisationen (RAVO) vor. Dieser Standardisierungsansatz wurde gewählt um sowohl technologische als auch paradigmatische Wechsel zu erlauben. Wir teilen unsere BemÜhungen in zwei Bereiche. Zuerst präsentieren wir einen Modellierungsansatz, um die Anforderungen und Komponenten der Virtuellen Organisation [1] zu identifiziert. Danach definieren wir einen generischen Rahmen, der auf dem Everything-as-a-Service Konzept aufbaut. Stakeholders sind ein wichtiges Element in jeder kooperationsunterstÜtzenden Umgebung [2] [3]. Daher haben wir ein neuartiges Schema fÜr Stakeholders entwickelt, die es erlaubt Beziehung zwischen Benutzer und Ressourcen in Form von Subjekten [1] [4] abzubilden. Zum Schluss werden diese Konzepte in Form konkreter Umsetzungen auf dem Gebiet des E-Learning und der Computational Intelligence untersucht. Die neuen Elemente der Stakeholders und Subjekt-Beziehungen wurden weiters in informelle Virtuelle Organisationen, sogenannten Sozialen Netzwerken, verifiziert [5]. Zur Evaluation des vorgestellten Ansatzes wurde schliesslich eine praktische Umsetzung, die auf RAVO basiert, unter dem Namen N2Sky als Masterarbeit an der Universität Wien durchgefÜhrt.“United we stand, divided we fall" is a well known saying. We are living in the era of virtual collaborations. Resources are logical and solutions are virtual. Advancement on conceptual and technological level has enhanced the way people communicate. Everything-as-a-Service once a dream, now becoming a reality. Problem nature has also been changed over the time. Today, e-Collaborations are applied to all the domains possible. Medical, engineering, meteorology, biology, chemistry, physics, earthquake and weather forecast, social networks and so on, all are using electronic platforms. Extensive data and computing resources are in need and assistance from human experts is also becoming essential. This puts a great responsibility on Information Technology (IT) researchers and developers to provide generic platforms where user can easily communicate and solve their problems. To realize this concept, distributed computing has offered many paradigms, e.g. cluster, grid, cloud computing. Virtual Organization (VO) is a logical orchestration of globally dispersed resources to achieve common goals. Existing paradigms and technology is used to form Virtual Organization, but lack of standards remained a critical issue for last two decades. Our research endeavor focuses on developing a standard for Virtual Organization building process. The proposed standardization process is a two phase activity. First phase provides requirement analysis and the second phase presents a Reference Architecture for Virtual Organization (RAVO). This form of standardization is chosen to accommodate both technological and paradigm shift. We categorize our efforts in two parts. First part consists of a pattern to identify the requirements and components of a Virtual Organization [1]. Second part details a generic framework based on the concept of Everything-as-a-Service. Stakeholders are an important entity in any collaborative environment [2] [3]. We developed a pattern for stakeholders and presented new relationship between user and resources in form of Subject [1] [4]. Finally, these concepts are materialized as a concrete framework in the domain of E-learning and Computational Intelligence. Stakeholders and Subject relationship are also verified in the domain of informal Virtual Organizations (e.g. Social Networks) [5]. For evaluation purpose an instance based on RAVO, named N2SKY [6] is developed by a master student at the University of Vienna

ADVANCED SLA MANAGEMENT IN CLOUD COMPUTING

The advent of high-performance technologies and the increase in volume of data used by organizations led to the need for migration from an internal structure to Cloud environment. The continuous development of tools, methods and techniques have expanded the understanding of the various functions, structures and processes related to Cloud Computing. However, the increase in computing power led to the development and use of more complex models, including this scope the complexity of Service Level Agreements (SLA). The need for understanding at a high level of SLAs established between customers and service providers in Cloud led to different studies on the definition and standardization of these agreements. Nowadays, cloud computing technologies are becoming more and more popular, especially with respect to data storage. However, the processes used to determine the Cloud Service Agreements do not consider the final customer\u2019s needs, considering only the supply capacity of the service provider. For these reasons, the development of service agreements that meets the needs of customers should be designed in order to increase the usability of Cloud environments, and enabling the discovery of new areas of application in accordance with market demand. In this context, the use of ontologies that describes the information that composes each type of service, and thus enable an understanding of the agreements reached, is configured as an approach to be considered. Moreover, the generalization and abstraction of information that can be observed in different services allows a broader vision for managing SLAs. For these reasons, this thesis aims to find innovative methods for the composition of Service Level Agreements in Cloud Computing. In particular, the methods presented allow demonstrate the convergence of several consolidated techniques in research on Cloud SLA using a new approach that considers new demands on Cloud and allows control of the established agreements, in addition to effectively ensure the application of the concept of XaaS (everything as a service). The originality of the approach allows the registration, search, composition and control of services in Cloud using the same structure. The new approach presented in this thesis allows the understanding of the impact of the new services requested by customers, giving the provider the possibility of simulating the use of the necessary resources to meet the new services\u2019 requests. From the presentation of a conceptual framework we can demonstrate the use of our approach through the examples of different situations presented in the real world and considering the new market possibilities

Cybersecurity issues in software architectures for innovative services

The recent advances in data center development have been at the basis of the widespread success of the cloud computing paradigm, which is at the basis of models for software based applications and services, which is the "Everything as a Service" (XaaS) model. According to the XaaS model, service of any kind are deployed on demand as cloud based applications, with a great degree of flexibility and a limited need for investments in dedicated hardware and or software components. This approach opens up a lot of opportunities, for instance providing access to complex and widely distributed applications, whose cost and complexity represented in the past a significant entry barrier, also to small or emerging businesses. Unfortunately, networking is now embedded in every service and application, raising several cybersecurity issues related to corruption and leakage of data, unauthorized access, etc. However, new service-oriented architectures are emerging in this context, the so-called services enabler architecture. The aim of these architectures is not only to expose and give the resources to these types of services, but it is also to validate them. The validation includes numerous aspects, from the legal to the infrastructural ones e.g., but above all the cybersecurity threats. A solid threat analysis of the aforementioned architecture is therefore necessary, and this is the main goal of this thesis. This work investigate the security threats of the emerging service enabler architectures, providing proof of concepts for these issues and the solutions too, based on several use-cases implemented in real world scenarios

Workload Analysis of Cloud Resources using Time Series and Machine Learning Prediction

© 2019 IEEE. Most of the businesses now-a-days have started using cloud platforms to host their software applications. A Cloud platform is shared resource that provides various services like software as a service (SAAS), infrastructure as a service (IAAS) or anything as a service (XAAS) that is required to develop and deploy any business application. These cloud services are provided as virtual machines (VM) that can handle the end user's requirements. The cloud providers must ensure efficient resource handling mechanisms for different time intervals to avoid wastage of resources. Auto-scaling mechanisms would take care of using these resources appropriately along with providing an excellent quality of service. Auto-scaling supports the cloud service providers achieve the goal of supplying the required resources automatically. It use methods that will calculate the number of requests and decides the resources to release based on workload. The workload consists of some quantity of application program running on the machine and usually some number of users connected to and communicating with the computer's applications. The researchers have used various approaches to perform autoscaling which is a process to predict the workload that is required to handle the end users request and provide required resources as Virtual Machines (VM) disruptively. Along with providing uninterrupted service, the businesses also only pay for the service they use, thus increasing the popularity of Cloud computing. Based on the workload identified the resources are provisioned. The resource provisioning techniques is a model used for enabling convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, applications, and services) required resources are released. In this regard, the aim of this paper is to develop a framework to predict the workload using deep learning which would be able to handle provisioning of cloud resources dynamically. This framework would handle the user request efficiently and allocate the required virtual machines. As a result, an efficient dynamic method of provisioning of cloud services would be implemented supporting both the cloud providers and users

A Lightweight Attribute-Based Access Control System for IoT.

The evolution of the Internet of things (IoT) has made a significant impact on our daily and professional life. Home and office automation are now even easier with the implementation of IoT. Multiple sensors are connected to monitor the production line, or to control an unmanned environment is now a reality. Sensors are now smart enough to sense an environment and also communicate over the Internet. That is why, implementing an IoT system within the production line, hospitals, office space, or at home could be beneficial as a human can interact over the Internet at any time to know the environment. 61% of International Data Corporation (IDC) surveyed organizations are actively pursuing IoT initiatives, and 6.8% of the average IT budgets is also being allocated to IoT initiatives. However, the security risks are still unknown, and 34% of respondents pointed out that data safety is their primary concern [1]. IoT sensors are being open to the users with portable/mobile devices. These mobile devices have enough computational power and make it di cult to track down who is using the data or resources. That is why this research focuses on proposing a dynamic access control system for portable devices in IoT environment. The proposed architecture evaluates user context information from mobile devices and calculates trust value by matching with de ned policies to mitigate IoT risks. The cloud application acts as a trust module or gatekeeper that provides the authorization access to READ, WRITE, and control the IoT sensor. The goal of this thesis is to offer an access control system that is dynamic, flexible, and lightweight. This proposed access control architecture can secure IoT sensors as well as protect sensor data. A prototype of the working model of the cloud, mobile application, and sensors is developed to prove the concept and evaluated against automated generated web requests to measure the response time and performance overhead. The results show that the proposed system requires less interaction time than the state-of-the-art methods

MACHS: Mitigating the Achilles Heel of the Cloud through High Availability and Performance-aware Solutions

Cloud computing is continuously growing as a business model for hosting information and communication technology applications. However, many concerns arise regarding the quality of service (QoS) offered by the cloud. One major challenge is the high availability (HA) of cloud-based applications. The key to achieving availability requirements is to develop an approach that is immune to cloud failures while minimizing the service level agreement (SLA) violations. To this end, this thesis addresses the HA of cloud-based applications from different perspectives. First, the thesis proposes a component’s HA-ware scheduler (CHASE) to manage the deployments of carrier-grade cloud applications while maximizing their HA and satisfying the QoS requirements. Second, a Stochastic Petri Net (SPN) model is proposed to capture the stochastic characteristics of cloud services and quantify the expected availability offered by an application deployment. The SPN model is then associated with an extensible policy-driven cloud scoring system that integrates other cloud challenges (i.e. green and cost concerns) with HA objectives. The proposed HA-aware solutions are extended to include a live virtual machine migration model that provides a trade-off between the migration time and the downtime while maintaining HA objective. Furthermore, the thesis proposes a generic input template for cloud simulators, GITS, to facilitate the creation of cloud scenarios while ensuring reusability, simplicity, and portability. Finally, an availability-aware CloudSim extension, ACE, is proposed. ACE extends CloudSim simulator with failure injection, computational paths, repair, failover, load balancing, and other availability-based modules