@article {Puliafito2019, title = {Fog computing for the Internet of Things: A survey}, journal = {ACM Transactions on Internet Technology - ACM}, volume = {19}, number = {2}, year = {2019}, note = {cited By 0}, publisher = {Association for Computing Machinery}, abstract = {

Research in the Internet of Things (IoT) conceives a world where everyday objects are connected to the Internet and exchange, store, process, and collect data from the surrounding environment. IoT devices are becoming essential for supporting the delivery of data to enable electronic services, but they are not sufficient in most cases to host application services directly due to their intrinsic resource constraints. Fog Computing (FC) can be a suitable paradigm to overcome these limitations, as it can coexist and cooperate with centralized Cloud systems and extends the latter toward the network edge. In this way, it is possible to distribute resources and services of computing, storage, and networking along the Cloud-to-Things continuum. Assuch, FC brings all the benefits of Cloud Computing (CC) closer to end (user) devices. This article presents a survey on the employment of FC to support IoT devices and services. The principles and literature characterizing FC are described, highlighting six IoT application domains that may benefit from the use of this paradigm. The extension of Cloud systems towards the network edge also creates new challenges and can have an impact on existing approaches employed in Cloud-based deployments. Research directions being adopted by the community are highlighted, with an indication of which of these are likely to have the greatest impact. An overview of existing FC software and hardware platforms for the IoT is also provided, along with the standardisation efforts in this area initiated by the OpenFog Consortium (OFC). {\textcopyright} 2019 Association for Computing Machinery.

}, keywords = {Application services, cloud computing, Digital storage, Electronic services, Fog, Fog computing, Internet of thing (IOT), Internet of Things, IOT applications, Resource Constraint, Software and hardwares, Surrounding environment, Surveys, Topological proximity}, issn = {15335399}, doi = {10.1145/3301443}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85063939776\&doi=10.1145\%2f3301443\&partnerID=40\&md5=49ad63c8f0f1685fd1d7365914fc86f5}, author = {Carlo Puliafito and Enzo Mingozzi and Francesco Longo and Antonio Puliafito and Omer Rana} } @article {549, title = {An IoT service ecosystem for Smart Cities: The $\#$SmartME project}, journal = {Internet of Things - Elsevier}, volume = {5}, year = {2019}, pages = {12-33}, abstract = {

$\#$SmartME has been one of the first initiatives in Italy to realize a Smart City through the use of open technologies. Thanks to the use of low cost sensor-powered devices scattered over the city area, different {\textquotedblleft}smart{\textquotedblright} services have been deployed having the Stack4Things framework as the common underlying middleware.\ In this paper, we present the results obtained after 2 years of project highlighting the vertical solutions that have been proposed in different areas ranging from environmental monitoring to parking management.

}, keywords = {Arduino, Blockchain, cloud computing, IoT, OpenStack, Smart city}, issn = {2542-6605}, doi = {https://doi.org/10.1016/j.iot.2018.11.004}, author = {Dario Bruneo and Salvatore Distefano and Maurizio Giacobbe and Antonino Longo Minnolo and Francesco Longo and Giovanni Merlino and Davide Mulfari and Alfonso Panarello and Giuseppe Patan{\`e} and Antonio Puliafito and Carlo Puliafito and Nachiket Tapas} } @proceedings {535, title = {Building a Smart City Service Platform in Messina with the $\#$SmartME Project}, journal = {The 32nd IEEE International Conference on Advanced Information Networking and Applications (IEEE AINA-2018)}, year = {2018}, month = {05/2018}, address = {Pedagogical University of Cracow, Poland}, abstract = {

Some words mark an era, and "Smart City" is definitely one of these. A Smart City is an urban area where the Information and Communication Technologies (ICT) are employed to improve citizens{\textquoteright} Quality of Life (QoL) in areas such as: mobility, urban surveillance, and energy management. Throughout this paper, we present the $\#$SmartME project, which aims to create an infrastructure and an ecosystem of "smart" services by exploiting existing devices, sensors, and actuators distributed in the city of Messina. We also present the Stack4Things framework, which is the management core of the $\#$SmartME project.

}, keywords = {$\#$SmartME, Arduino, Blockchain, cloud computing, IoT, OpenData, OpenStack, Smart city, Stack4Things}, author = {Dario Bruneo and Sebastiano Chillari and Salvatore Distefano and Maurizio Giacobbe and Antonino Longo Minnolo and Francesco Longo and Giovanni Merlino and Davide Mulfari and Alfonso Panarello and Giuseppe Patan{\`e} and Antonio Puliafito and Carlo Puliafito and Marco Scarpa and Nachiket Tapas and Giancarlo Visalli} } @article {Dautov201829822, title = {Data Processing in Cyber-Physical-Social Systems Through Edge Computing}, journal = {IEEE Access - IEEE}, volume = {6}, year = {2018}, note = {cited By 0}, pages = {29822-29835}, publisher = {Institute of Electrical and Electronics Engineers Inc.}, abstract = {

Cloud and Fog computing have established a convenient and widely adopted approach for computation offloading, where raw data generated by edge devices in the Internet of Things (IoT) context is collected and processed remotely. This vertical offloading pattern, however, typically does not take into account increasingly pressing time constraints of the emerging IoT scenarios, in which numerous data sources, including human agents (i.e., Social IoT), continuously generate large amounts of data to be processed in a timely manner. Big data solutions could be applied in this respect, provided that networking issues and limitations related to connectivity of edge devices are properly addressed. Although edge devices are traditionally considered to be resource-constrained, main limitations refer to energy, networking, and memory capacities, whereas their ever-growing processing capabilities are already sufficient to be effectively involved in actual (big data) processing. In this context, the role of human agents is no longer limited to passive data generation, but can also include their voluntary involvement in relatively complex computations. This way, users can share their personal computational resources (i.e., mobile phones) to support collaborative data processing, thereby turning the existing IoT into a global cyber-physical-social system (CPSS). To this extent, this paper proposes a novel IoT/CPSS data processing pattern based on the stream processing technology, aiming to distribute the workload among a cluster of edge devices, involving mobile nodes shared by contributors on a voluntary basis, and paving the way for cluster computing at the edge. Experiments on an intelligent surveillance system deployed on an edge device cluster demonstrate the feasibility of the proposed approach, illustrating how its distributed in-memory data processing architecture can be effective. {\textcopyright} 2013 IEEE.

}, keywords = {Apache NiFi, Big Data, Cameras, Cellular telephone systems, cloud computing, Cluster computing, Computer architecture, Cyber physical social systems, Cyber Physical System, Edge computing, Fog computing, Horizontal and Vertical Offloading, Internet of Things, Media streaming, Network security, Servers, Stream processing, Streaming media}, issn = {21693536}, doi = {10.1109/ACCESS.2018.2839915}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85047619039\&doi=10.1109\%2fACCESS.2018.2839915\&partnerID=40\&md5=48b52a73084c2f6396c4ce1dd6a690f4}, author = {Rustem Dautov and Salvatore Distefano and Dario Bruneo and Francesco Longo and Giovanni Merlino and Antonio Puliafito} } @proceedings {548, title = {An Implementation Of InfluxDB For Monitoring And Analytics In Distributed IoT Environments}, journal = {Science of Electronics, Technologies of Information and Telecommunication Conference (SETIT 2018)}, year = {2018}, month = {12/2018}, publisher = {Springer}, address = {Hammamet, Tunisia}, keywords = {cloud computing, InfluxDB, Internet of Things, smart environments, time series database}, author = {Maurizio Giacobbe and Chakib Chaouch and Marco Scarpa and Antonio Puliafito} } @article {Dautov20181475, title = {Metropolitan intelligent surveillance systems for urban areas by harnessing IoT and edge computing paradigms}, journal = {Software - Practice and Experience - John Wiley \& Sons, Ltd.}, volume = {48}, number = {8}, year = {2018}, note = {cited By 0}, pages = {1475-1492}, publisher = {John Wiley and Sons Ltd}, abstract = {

Recent technological advances led to the rapid and uncontrolled proliferation of intelligent surveillance systems (ISSs), serving to supervise urban areas. Driven by pressing public safety and security requirements, modern cities are being transformed into tangled cyber-physical environments, consisting of numerous heterogeneous ISSs under different administrative domains with low or no capabilities for reuse and interaction. This isolated pattern renders itself unsustainable in city-wide scenarios that typically require to aggregate, manage, and process multiple video streams continuously generated by distributed ISS sources. A coordinated approach is therefore required to enable an interoperable ISS for metropolitan areas, facilitating technological sustainability to prevent network bandwidth saturation. To meet these requirements, this paper combines several approaches and technologies, namely the Internet of Things, cloud computing, edge computing and big data, into a common framework to enable a unified approach to implementing an ISS at an urban scale, thus paving the way for the metropolitan intelligent surveillance system (MISS). The proposed solution aims to push data management and processing tasks as close to data sources as possible, thus increasing performance and security levels that are usually critical to surveillance systems. To demonstrate the feasibility and the effectiveness of this approach, the paper presents a case study based on a distributed ISS scenario in a crowded urban area, implemented on clustered edge devices that are able to off-load tasks in a {\textquotedblleft}horizontal{\textquotedblright} manner in the context of the developed MISS framework. As demonstrated by the initial experiments, the MISS prototype is able to obtain face recognition results 8 times faster compared with the traditional off-loading pattern, where processing tasks are pushed {\textquotedblleft}vertically{\textquotedblright} to the cloud. Copyright {\textcopyright} 2018 John Wiley \& Sons, Ltd.

}, keywords = {Big Data, cloud computing, Distributed Smart Cameras, Edge computing, Face recognition, Information management, Intelligent surveillance systems, Internet of Things, monitoring, Multiple video streams, Network security, Public safety and securities, Security systems, Smart city, Stack4Things, Stream processing, Surveillance systems, Technological advances}, issn = {00380644}, doi = {10.1002/spe.2586}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85049578094\&doi=10.1002\%2fspe.2586\&partnerID=40\&md5=25de910451975bb24c9cfbdf6ca69066}, author = {Rustem Dautov and Salvatore Distefano and Dario Bruneo and Francesco Longo and Giovanni Merlino and Antonio Puliafito and Rajkumar Buyya} } @proceedings {505, title = {A Context-aware Strategy To Properly Use IoT-Cloud Services}, journal = {2017 IEEE International Conference on Smart Computing (SMARTCOMP)}, year = {2017}, month = {05/2017}, pages = {1-6}, publisher = {IEEE}, address = {Hong Kong - China}, abstract = {

Nowadays, we can talk about the Internet of Things (IoT) and Cloud computing union to indicate a new generation of distributed system.

An IoT-Cloud system mainly consists of a set of smart objects which are interconnected through the Internet with a remote Cloud infrastructure, platform, or software.

It allows to achieve new benefits in several contexts, such as smart cities and industrial businesses.

In this paper we propose a context-aware strategy focused on the correct use of the IoT-Cloud services. In particular, a use case driven scenario and a three-step algorithm to define the strategy are presented and discussed.

}, keywords = {Big Data, cloud computing, context-aware systems, Internet of Things, multi criteria decision making, smart cities, smart environments, smart factories}, doi = {10.1109/SMARTCOMP.2017.7946976}, author = {Maurizio Giacobbe and Antonio Puliafito and Riccardo Di Pietro and Marco Scarpa} } @proceedings {486, title = {An Energy-Aware Brokering Algorithm To Improve Sustainability In Community Cloud}, journal = {Proceedings of the 6th International Conference on Smart Cities and Green ICT Systems (SMARTGREENS 2017)}, volume = {1}, year = {2017}, month = {04/2017}, pages = {166-173}, publisher = {Institute for Systems and Technologies of Information, Control and Communication (INSTICC)}, address = {Porto, Portugal}, abstract = {

Cloud computing is a paradigm for large scale distributed infrastructures, platforms or software services which represents a hot topic in Information Technology (IT) recently in both industrial and academic areas. Its use is motivated by the possibility to promote a new economy of scale in different contexts. Along with the well-known public, private and hybrid Cloud models, the Community Cloud is an emerging concept based on a deployment model in which a Cloud infrastructure allows a specific community of consumers to share interests, goals and responsibilities. It can be owned and managed by the community, by a third party, or a combination of them. In such scenario, new low-carbon strategies at Cloud sites are necessary to allow those latter to reduce the consumption in presence of a massive exploitation of IT services. Therefore, balancing performances with both sustainability and cost saving concepts is a challenge. In this paper, we present a low carbon strategy designed to make the best choice in resources allocation, based on sustainability, availability and costs. The proposed energy-aware Brokering Algorithm (eBA) allows to push down carbon dioxide emissions through the Community Cloud ecosystem, by running instances at the most convenient sites.

}, keywords = {cloud computing, Community Cloud, Energy-aware Brokering, Green Cloud, Low Carbon, Resource allocation, Sustainability, Virtualization}, issn = {978-989-758-241-7}, doi = {10.5220/0006300201660173}, url = {http://www.scitepress.org/DigitalLibrary/PublicationsDetail.aspx?ID=8XfUdAkq8Pk=\&t=1}, author = {Maurizio Giacobbe and Marco Scarpa and Riccardo Di Pietro and Antonio Puliafito} } @proceedings {Dautov2018792, title = {Pushing intelligence to the edge with a stream processing architecture}, journal = {Proceedings - 2017 IEEE International Conference on Internet of Things, IEEE Green Computing and Communications, IEEE Cyber, Physical and Social Computing, IEEE Smart Data, iThings-GreenCom-CPSCom-SmartData 2017}, year = {2017}, note = {cited By 3; Conference of Joint 10th IEEE International Conference on Internet of Things, iThings 2017, 13th IEEE International Conference on Green Computing and Communications, GreenCom 2017, 10th IEEE International Conference on Cyber, Physical and Social Computing, CPSCom 2017 and the 3rd IEEE International Conference on Smart Data, Smart Data 2017 ; Conference Date: 21 June 2017 Through 23 June 2017; Conference Code:134517}, pages = {792-799}, publisher = {Institute of Electrical and Electronics Engineers Inc.}, address = {Exeter, UK - 21-23 June 2017}, abstract = {

The cloud computing paradigm underpins the Internet of Things (IoT) by offering a seemingly infinite pool of resources for processing/storing extreme amounts of data generated by complex IoT systems. The cloud has established a convenient and widely adopted approach, where raw data are vertically offloaded to cloud servers from resource-constrained edge devices, which are only seen as simple data generators, not capable of performing more sophisticated processing activities. However, there are more and more emerging scenarios, where the amount of data to be transferred over the network to the cloud is associated with increased network latency, making the results of the computation obsolete. As various categories of edge devices are becoming more and more powerful in terms of hardware resources - specifically, CPU and memory - the established way of off-loading computation to the cloud is not always seen as the most convenient approach. Accordingly, this paper presents a Stream Processing architecture for spreading workload among a local cluster of edge devices to process data in parallel, thus achieving faster execution and response times. The experimental results suggest that such a distributed in-memory approach to data processing at the very edge of a computational network has a potential to address a wide range of IoT-related scenarios. {\textcopyright} 2017 IEEE.

}, keywords = {Apache NiFi, cloud computing, Cluster computing, Computational networks, Data handling, Edge computing, Green Computing, Hardware resources, Horizontal offloading, Internet of thing (IOT), Internet of Things, Memory architecture, Network architecture, Network latencies, Processing activity, Stream processing}, isbn = {9781538630655}, doi = {10.1109/iThings-GreenCom-CPSCom-SmartData.2017.121}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85047094836\&doi=10.1109\%2fiThings-GreenCom-CPSCom-SmartData.2017.121\&partnerID=40\&md5=4e5a4b0eaffa179565af183066520cdf}, author = {Rustem Dautov and Salvatore Distefano and Dario Bruneo and Francesco Longo and Giovanni Merlino and Antonio Puliafito} } @proceedings {423, title = {Characterizing IoT Cloud Federation}, journal = {2016 30th International Conference on Advanced Information Networking and Applications Workshops (WAINA) - Workshop on Cloud Computing Project and Initiatives - CCPI{\textquoteright}16}, year = {2016}, publisher = {IEEE Computer Society}, address = {Le R{\'e}gent Congress Centre, Crans-Montana, Switzerland}, abstract = {

The advent of both Cloud computing and Internet of Things (IoT) is changing the way of conceiving information and communication systems. Generally, we talk about IoT Cloud to indicate a new type of distributed system consisting of a set of smart devices interconnected with a remote Cloud infrastructure, platform, or software through the Internet and able to provide IoT as a Service (IoTaaS).\ In this paper, we discuss the near future evolution of IoT Clouds towards federated ecosystems, where IoT providers cooperate to offer more flexible services.\ Moreover, we present a general three-layer IoT Cloud Federation architecture, highlighting new business opportunities and challenges.\ 

}, keywords = {cloud computing, containers, federation, IoT, virtualisation}, issn = {978-1-5090-2461-2/16}, doi = {10.1109/WAINA.2016.152}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=7471179}, author = {Antonio Celesti and Maria Fazio and Maurizio Giacobbe and Antonio Puliafito and Massimo Villari} } @proceedings {434, title = {Exploring Container Virtualization in IoT Clouds}, journal = {2016 International Conference on Smart Computing Workshops (SMARTCOMP Workshops)}, year = {2016}, pages = {1-6}, publisher = {IEEE Computer Society}, address = {May 18, 2016 {\textendash} St. Louis, Missouri}, abstract = {

The advent of both Cloud computing and Internet of Things (IoT) is changing the way of conceiving information and communication systems. Generally, we talk about IoT Cloud to indicate a new type of distributed system consisting of a set of smart objects, e.g., single board computers running Linux-based operating systems, interconnected with a remote Cloud infrastructure, platform, or software through the Internet and able to provide IoT as a Service (IoTaaS). In this context, container-based virtualization is a lightweight alternative to the hypervisor-based approach that can be adopted on smart objects, for enhancing the IoT Cloud service provisioning.\ 
In particular, considering different IoT application scenarios, container-based virtualization allows IoT Cloud providers to deploy and customize in a flexible fashion pieces of software on smart objects. In this paper, we explore the container-based virtualization on smart objects in the perspective of a IoT Cloud scenarios analyzing its advantages and performances.

}, keywords = {cloud computing, containers, IoT, Virtualization}, issn = {978-1-5090-0898-8}, doi = {10.1109/SMARTCOMP.2016.7501691}, url = {http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=7501691}, author = {Antonio Celesti and Davide Mulfari and Maria Fazio and Massimo Villari and Antonio Puliafito} } @proceedings {443, title = {Improving Desktop as a Service in OpenStack}, journal = {The 21st IEEE Symposium on Computers and Communications (ISCC{\textquoteright}16)}, year = {2016}, publisher = {IEEE Computer Society}, address = {Washington, DC}, abstract = {

Nowadays, in the Cloud computing panorama, users access their Virtual Machines (VMs) using SSH or web-based remote desktop clients. In this context, OpenStack is one of the major open-source solutions for creating and managing Infrastructure as a Service (IaaS) Cloud providers. Typically, OpenStack tenants graphically control their VMs using noVNC, i.e., the default web-based remote desktop client integrated in its web dashboard. Unfortunately, up to now, considering noVNC, the video update response time is not so good and the audio redirection has not been supported yet. In this paper, we discuss how can be possible to improve the Desktop as a Service (DaaS) in OpenStack Clouds by integrating alternative solutions based on both the Remote Frame Buffer (RFB) protocol and the Remote Desktop Protocol (RDP). Experiments highlight, from an objective point of view, the behaviour of different solutions, providing useful hints to software architects and developers.

}, keywords = {cloud computing, OpenStack, Remote desktop, Virtual Machine}, author = {Antonio Celesti and Davide Mulfari and Maria Fazio and Massimo Villari and Antonio Puliafito} } @proceedings {Bruneo2017222, title = {IoT-cloud authorization and delegation mechanisms for ubiquitous sensing and actuation}, journal = {2016 IEEE 3rd World Forum on Internet of Things, WF-IoT 2016}, year = {2016}, note = {cited By 0; Conference of 3rd IEEE World Forum on Internet of Things, WF-IoT 2016 ; Conference Date: 12 December 2016 Through 14 December 2016; Conference Code:126414}, pages = {222-227}, publisher = {Institute of Electrical and Electronics Engineers Inc.}, address = {Reston; United States; 12-14 December 2016}, abstract = {

In the roadmap for the implementation of ubiquitous computing, ubiquitous sensing and actuation is a milestone still to be reached. It refers to providing sensing and actuation facilities anytime and everywhere. This does not just imply to interconnect sensors and actuators through the Internet, but also and mainly to provide this facilities. IoT-Cloud computing paradigms such as the sensing and actuation as a service one could be a proper way to address this problem. In past work we developed an SAaaS framework extending OpenStack with specific functionalities for resource constrained nodes, Stack4Things. In this paper we focus on access control, authorization and delegation mechanisms which are basic mechanisms for the implementation of the UbSA vision. Thus starting from Stack4Things, we describe how we adapted and extended mechanisms provided by OpenStack, with specific regard to Keystone, with new functionalities for delegation and access control. A use case in the smart city scenario of $\#$SmartME describes the proposed solution in practice. {\textcopyright} 2016 IEEE.

}, keywords = {Access control, Arches, Basic mechanism, cloud computing, Delegation, Delegation mechanisms, Interconnect sensors, Internet of Things, Keystone, OpenStack, Platform as a Service (PaaS), Resource constrained nodes, Sensing and Actuation as a Service, Smart city, Ubiquitous computing}, isbn = {9781509041305}, doi = {10.1109/WF-IoT.2016.7845494}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85015210244\&doi=10.1109\%2fWF-IoT.2016.7845494\&partnerID=40\&md5=055a280adfbce85756d94736e2b82c55}, author = {Dario Bruneo and Salvatore Distefano and Francesco Longo and Giovanni Merlino and Antonio Puliafito} } @proceedings {479, title = {Re-Powering Service Provisioning Through Virtual Machine Migration in Federated Cloud Environments: An Algorithm Combining Energy Sustainability and Cost-Saving Strategies}, journal = {The 4th International Workshop on CLoud for IoT (CLIoT 2016)}, volume = {Advances in Service-Oriented and Cloud Computing}, year = {2016}, month = {01/2018}, pages = {19-33}, publisher = {Springer International Publishing}, address = {Vienna, Austria}, abstract = {

Cloud federation offers new business models to enforce more flexible energy management strategies. Typically, an independent Cloud provider is exclusively bounded to the specific energy supplier powering its data center. The situation radically change if we consider a federation of cooperating Cloud providers. In such a context a proper migration of virtual machines among providers can lead to global energy sustainability and cost-saving strategies.\ 
In this paper, we discuss a decision algorithm, for Cloud federation brokerage, able to combine these two strategies. More specifically, we present a Multi-Criteria Decision Making (MCDM) algorithm able to discover the most convenient Cloud provider candidates to join a particular energy-aware federation. In the end, by modelling different possible real Cloud providers, we demonstrate how the algorithm can accommodate different Cloud federation scenarios characterized by particular energy-aware parameters.

}, keywords = {cloud brokerage, cloud computing, cloud federation, energy cost-saving, Energy Efficiency, energy management, Energy Sustainability}, issn = {978-3-319-72125-5}, doi = {10.1007/978-3-319-72125-5_2}, author = {Maurizio Giacobbe and Antonio Celesti and Maria Fazio and Massimo Villari and Antonio Puliafito} } @article {10.4108/cs.1.1.e4, title = {Achieving Assistive Technology Systems Based on IoT Devices in Cloud Computing}, journal = {EAI Endorsed Transactions on Cloud Systems}, volume = {15}, number = {1}, year = {2015}, month = {2}, publisher = {ICST}, keywords = {Assistive Technology, cloud computing, embedded systems, human computer interaction, Internet of Things, Users with disabilities.}, issn = {2410-6895}, doi = {10.4108/cs.1.1.e4}, author = {Davide Mulfari and Antonio Celesti and Maria Fazio and Massimo Villari and Antonio Puliafito} } @proceedings {Bruneo2015797, title = {Analytical Modeling of Reactive Autonomic Management Techniques in IaaS Clouds}, journal = {Proceedings - 2015 IEEE 8th International Conference on Cloud Computing, CLOUD 2015}, year = {2015}, note = {cited By 2; Conference of 8th IEEE International Conference on Cloud Computing, CLOUD 2015 ; Conference Date: 27 June 2015 Through 2 July 2015; Conference Code:116940}, pages = {797-804}, publisher = {Institute of Electrical and Electronics Engineers Inc.}, address = {New York (USA)}, abstract = {

Cloud computing infrastructures provide services to a wide number of users whose behavior can deeply change at the occurrence of particular events. To correctly handle such situations a cloud infrastructure have to be reconfigured in a way that does not cause degradation in the overall performance. Otherwise, the quality of service specified in the service level agreement could be violated. To prevent such situations, the infrastructure could be organized as an autonomic system where self-adaptation and self-configuration techniques are implemented. Appropriate design choices become important in order not to fail in this goal. We propose a technique, based on a Petri net model and a specific analytical analysis approach, to represent Infrastructure-as-a-Service (IaaS) systems in the case in which the load conditions can suddenly change and reactive autonomic management techniques are applied to mitigate the consequences of the change. The model we propose is able to appropriately evaluate performance metrics in such critical situations making it suitable as a design tool for IaaS cloud systems. {\textcopyright} 2015 IEEE.

}, keywords = {Autonomic management, cloud computing, Cloud computing infrastructures, Cloud infrastructures, Iaas clouds, Industrial management, Infrastructure as a service (IaaS), Performance metrics, Petri nets, Quality of service, Resiliency, Service Level Agreements, Stochastic reward nets, Stochastic systems}, isbn = {9781467372879}, doi = {10.1109/CLOUD.2015.110}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84960155425\&doi=10.1109\%2fCLOUD.2015.110\&partnerID=40\&md5=2aa09923889aea0bc667deb1d6d250d8}, author = {Dario Bruneo and Francesco Longo and Rahul Ghosh and Marco Scarpa and Antonio Puliafito and Kishor Trivedi} } @proceedings {161, title = {Costs of a Federated and Hybrid Cloud Environment Aimed at MapReduce Video Transcoding}, journal = {2015 IEEE Symposium on Computers and Communication (ISCC), Larnaca Cyprus}, year = {2015}, month = {2015}, pages = {258-263}, publisher = {IEEE Computer Society}, address = {Larnaca, Cyprus}, abstract = {
In this paper we investigate the applicability of the federation among several Cloud platform, demonstrating that a federated environment provides evident benefits despite the costs for the setup and maintainance of the federation itself. Also, we propose a new solution able to manage resource allocation in federated Clouds where resource requests occur in a dynamic way. We adopt such a solution to setup distributed Hadoop nodes of virtual clusters for the parallel MapReduce processing of large data sets. To increase their capabilities, Cloud Providers establish a federation relationship, making the Hadoop-based Cloud platforms much more performing than in the isolate case, adding a further level of parallelization in service provisioning. The results analyzed in the referece use case, that is a video transcoding using the MapReduce paradigm in a federated fashion, show how the federation costs in terms of delays and overhead are low in comparison with the service provisioning costs, and also highlight how federation makes the offered Cloud service more streamlined and fast.
}, keywords = {Apache Hadoop, Big Data, CLEVER, cloud computing, HDFS, Horizontal Federation, IEEE P2302, MapReduce}, doi = {10.1109/ISCC.2015.7405525}, url = {http://ieeexplore.ieee.org/xpl/login.jsp?tp=\&arnumber=7405525\&url=http\%3A\%2F\%2Fieeexplore.ieee.org\%2Fxpls\%2Fabs_all.jsp\%3Farnumber\%3D7405525}, author = {Alfonso Panarello and Maria Fazio and Antonio Celesti and Massimo Villari and Antonio Puliafito} } @inbook {291, title = {Embedded systems for supporting computer accessibility}, booktitle = {Association for the Advancement of Assistive Technology in Europe (AAATE)}, number = {217: Assistive Technology}, year = {2015}, pages = {378-385}, publisher = {IOS Press}, organization = {IOS Press}, edition = {Series: Studies in Health Technology and Informatics}, address = {Budapest, Hungary}, abstract = {Nowadays, customized AT software solutions allow their users to interact with various kinds of computer systems. Such tools are generally available on personal devices (e.g., smartphones, laptops and so on) commonly used by a person with a disability. In this paper, we investigate a way of using the aforementioned AT equipments in order to access many different devices without assistive preferences. The solution takes advantage of open source hardware and its core component consists of an affordable Linux embedded system: it grabs data coming from the assistive software, which runs on the user{\textquoteright}s personal device, then, after processing, it generates native keyboard and mouse HID commands for the target computing device controlled by the end user. This process supports any operating system available on the target machine and it requires no specialized software installation; therefore the user with a disability can rely on a single assistive tool to control a wide range of computing platforms, including conventional computers and many kinds of mobile devices, which receive input commands through the USB HID protocol.}, keywords = {Assistive Technology, cloud computing, IoT}, isbn = {978-1-61499-565-4 (print) | 978-1-61499-566-1 (online)}, doi = {10.3233/978-1-61499-566-1-378}, url = {http://ebooks.iospress.nl/publication/40681}, author = {Davide Mulfari and Antonio Celesti and Maria Fazio and Massimo Villari and Antonio Puliafito} } @proceedings {Bruneo201524, title = {Enabling collaborative development in an open stack testbed: The cloud wave use case}, journal = {Proceedings of the 7th International Workshop on Principles of Engineering Service-Oriented and Cloud Systems (PESOS 2015)}, year = {2015}, note = {cited By 0; Conference of 7th International Workshop on Principles of Engineering Service-Oriented and Cloud Systems, PESOS 2015 ; Conference Date: 23 May 2015; Conference Code:117285}, pages = {24-30}, publisher = {IEEE Computer Society}, address = {Florence, Italy, 23 May 2015 - }, abstract = {

The Cloud Wave project embodies a challenging set of goals, including the development of software components that have to be integrated into a single multi-layer Cloud stack based on Open Stack, while cutting across the Infrastructure-as-a-Service, Platform-as-a-Service, and Software-as-a-Service levels by targeting layer-spanning issues such as Feedback-Driven Development and Coordinated Adaptation. A DevOps-ready test bed environment should allow project partners to exert full control over deployed compo entry and collaborate on development. Goals include providing a flexible infrastructure capable of emulating several multi-node Cloud environments, as well as enabling the automatic deployment of Cloud Wave artifacts into such environment in order to simplify integration activities. This paper takes a snapshot of the current situation with regards to the design and implementation of such a setup, trying to gain relevant insight out of this effort. {\textcopyright} 2015 IEEE.

}, keywords = {Automatic deployments, cloud computing, Collaborative development, Continuous integrations, Design and implementations, DevOps, Distributed computer systems, Infrastructure as a service (IaaS), Integration, OpenStack, Platform as a Service (PaaS), Software as a service (SaaS), Test bed environment, Testbeds, Virtual infrastructures}, isbn = {9781479919345}, issn = {21567921}, doi = {10.1109/PESOS.2015.12}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84955273627\&partnerID=40\&md5=3fed56f69ce2ffdc46abcdf129e1e355}, author = {Dario Bruneo and Francesco Longo and Giovanni Merlino and Nicola Peditto and Carmelo Romeo and Fabio Verboso and Antonio Puliafito} } @proceedings {221, title = {A Federated MapReduce-based Video Transcoding System to Face the Future Massive Video-Selfie Sharing Trend}, journal = {Fourth European Conference on Service-Oriented and Cloud Computing (ESOCC 2015) - 3rd International Workshop on Cloud for IoT}, year = {2015}, publisher = {Springer International Publishing}, edition = {Communications in Computer and Information Science (CCSI)}, abstract = {
The massive use of mobile devices and social networks is causing the birth of a new compulsive users{\textquoteright} behaviour. The activity photo selfie sharing is gradually turning into video selfie. These videos will be transcoded into multiple formats to support different visualization mode. We think there will be the need to have systems that can support, in a fast, efficient and scalable way, the millions of requests for video sharing and viewing. We think that a single Cloud Computing services provider cannot alone cope with this huge amount of incoming data (Big Data), so in this paper we propose a Cloud Federation-based system that exploiting the Hadoop MapReduce paradigm performs the video transcoding in multiple format and its distribution in a fastest and most efficient possible way. Experimental results highlight the major factors involved for job deployment in a federated Cloud environment and the efficiency of the proposed system.
}, keywords = {Adaptive Streaming, Apache Hadoop, Big Data, CLEVER, cloud computing, HDFS, Horizontal Federation, IEEE P2302, MapReduce}, author = {Alfonso Panarello and Antonio Celesti and Maria Fazio and Massimo Villari and Antonio Puliafito} } @proceedings {7092964, title = {How to Enhance Cloud Architectures to Enable Cross-Federation: Towards Interoperable Storage Providers}, journal = { IEEE International Conference on Cloud Engineering (IC2E), Tempe, AZ, USA}, year = {2015}, month = {March}, pages = {480-486}, publisher = {IEEE Computer Society}, address = {Washington D.C.}, keywords = {Big Data, Big Data storage, CLEVER, CLEVER message oriented middleware, cloud architectures, cloud computing, cloud storage market, cross-federation, Ecosystems, federated cloud ecosystem, federation, Hadoop, Hadoop distribute file system, HDFS, inter-domain communication management, interoperable storage providers, Message systems, middleware, MOM, Protocols, public domain software, Resource management, Servers, small-medium cloud storage providers, Storage, storage management, XML, XMPP}, doi = {10.1109/IC2E.2015.80}, url = {http://conferences.computer.org/IC2E/2015/index.htm}, author = {Maria Fazio and Antonio Celesti and Massimo Villari and Antonio Puliafito} } @proceedings {345, title = {Identity Management in IoT Clouds: a FIWARE Case of Study}, journal = {2015 IEEE Conference on Communications and Network Security (CNS) - 1st Workshop on Security and Privacy in the Cloud (SPC 2015)}, year = {2015}, pages = {680-684}, publisher = {IEEE Computer Society}, address = {Florence, Italy, September 30th, 2015}, abstract = {

Nowadays, the combination between Cloud computing and Internet of Things (IoT) is pursuing new levels of efficiency in delivering services, representing a tempting business opportunity for ICT operators of increasing their revenues. However, security is seen as one of the major factors that slows down the rapid and large scale adoption and deployment of both the IoT and Cloud computing.\ 
In this paper, considering such an IoT Cloud scenario, we present an authentication model that allow IoT devices to join IoT Clouds and users to access the system. Moreover, we discuss the issues involved in applying our authentication models in a real IoT Cloud based on the FIWARE technology.

}, keywords = {authentication, cloud computing, FIWARE, Internet of Things, security}, issn = {978-1-4673-7876-5}, url = {http://www.zurich.ibm.com/spc2015/}, author = {Luciano Barreto and Antonio Celesti and Massimo Villari and Maria Fazio and Antonio Puliafito} } @article {Bruneo20153052, title = {Modeling and Evaluation of Energy Policies in Green Clouds}, journal = {IEEE Transactions on Parallel and Distributed Systems}, volume = {26}, number = {11}, year = {2015}, note = {cited By 0}, pages = {3052-3065}, publisher = {IEEE Computer Society}, abstract = {

Following the as-a-service philosophy, a cloud service provider offers computing utilities in the form of virtual resources instantiated on top of a physical infrastructure. In order to meet business requirements still providing high-quality services, performance evaluation needs to be carefully carried out with the aim of optimizing data center utilization and increasing user satisfaction. In this context, power efficiency plays a critical role pushing service providers towards the application of innovative green strategies. In this paper, we present an analytical framework, based on stochastic reward nets, that allows to evaluate different resource allocation policies in a green cloud. A use case is shown in order to illustrate the approach, modeling scattering and saturation allocation policies and comparing them to a purely physical data center scenario. A validation of the proposed model against the CloudSim framework is presented and several numerical results are provided, demonstrating the effectiveness of the approach as a powerful tool for a cloud service provider to perform well-informed decisions about theresource allocation policies to be enforced. {\textcopyright} 1990-2012 IEEE.

}, keywords = {Allocation policies, Business requirement, cloud computing, Cloud service providers, Distributed database systems, Green Computing, High quality service, Performance evaluation, Quality control, Resource allocation, Resource allocation policy, Stochastic reward nets, Stochastic systems}, issn = {10459219}, doi = {10.1109/TPDS.2014.2364194}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84944075521\&partnerID=40\&md5=ee939ccd602bffca9ab90abdfd8285d9}, author = {Dario Bruneo and Audric Lhoas and Francesco Longo and Antonio Puliafito} } @proceedings {348, title = {A Sustainable Energy-Aware Resource Management Strategy for IoT Cloud Federation}, journal = {The first IEEE International Symposium on Systems Engineering (ISSE)}, volume = {IEEE First International Symposium on Systems Engineering 2015 Proceedings}, year = {2015}, month = {09/2015}, pages = {170-175}, publisher = {IEEE Computer Society}, address = {Roma, Italy}, abstract = {

The advent of both Cloud computing and Internet of Things (IoT) is changing the way to conceive distributed systems. Nowadays, we can talk about IoT Cloud to indicate a new type of distributed system consisting of a set of smart IoT devices or sensors interconnected with a remote Cloud infrastructure, platform, or software. Energy sustainability in IoT Cloud providers offers new tempting business opportunities for organizations, but at the same time it raises new challenges. In this paper, a flexible IoT Cloud federation energy management strategy is presented for optimizing the allocation of geographically localized smart sensors. We define the concept of IoT Cloud Federation as a mesh of IoT Cloud providers that are interconnected to provide a universal decentralized sensing and actuating environment where everything is driven by constraints and agreements in a ubiquitous infrastructure.\ In particular, a dynamic algorithm able to improve energy sustainability in a federated IoT Cloud ecosystem is discussed. In addition, we analyze a use-case driven strategy that allows both IoT Cloud providers and brokers to determine the paths to reach possible destination IoT devices in which computational resources should be dynamically migrated in order to push down the energy consumption due to IoT distributed applications.

}, keywords = {cloud computing, Energy Efficiency, Energy Sustainability, federation, Green Computing, Internet of Things, Virtual Sensors}, issn = {978-1-4799-1919-2}, author = {Maurizio Giacobbe and Antonio Celesti and Maria Fazio and Massimo Villari and Antonio Puliafito} } @article {351, title = {Towards the Integration Between IoT and Cloud Computing: An Approach for the Secure Self-Configuration of Embedded Devices}, journal = {International Journal of Distributed Sensor Networks}, volume = {2015}, year = {2015}, month = {2016}, pages = {1-9}, abstract = {

The secure boot up and setup of Internet of Things\ (IoT) devices connected over the Cloud represents a challenging open issue. This paper deals with the automatic configuration\ of IoT devices in a secure way through the Cloud, in order\ to provide new added-value services. After a discussion on the\ limits of current IoT and Cloud solutions in terms of secure selfconfiguration,\ we present a Cloud-based architecture that allows\ IoT devices to interact with several federated Cloud providers.\ In particular, we present two possible scenarios, i.e., single Cloud\ and a federated Cloud environments interacting with IoT devices\ and we address specific issues of both. Moreover, we present\ several design highlights on how to operate considering real open\ hardware and software products already available in the market.

}, keywords = {cloud computing, federation, IoT, security, self-configuration}, doi = {http://dx.doi.org/10.1155/2015/286860}, url = {http://www.hindawi.com/journals/ijdsn/2015/286860/}, author = {Antonio Puliafito and Antonio Celesti and Massimo Villari and Maria Fazio} } @proceedings {Bruneo2014, title = {CloudWave: Where adaptive cloud management meets DevOps}, journal = {Proceedings of the 5th IEEE International Workshop on Performance Evaluation of Communications in Distributed Systems and Web based Service Architectures (PEDISWESA) Co-located with the 19th International Symposium on Computers and Communications (ISCC)}, year = {2014}, note = {cited By 0; Conference of ISCC 2014 Workshop - 5th IEEE International Workshop on Performance Evaluation of Communications in Distributed Systems and Web based Service Architectures, PEDISWESA 2014 ; Conference Date: 23 June 2014 Through 26 June 2014; Conference Code:108095}, publisher = {IEEE Computer Society}, address = {Island of Madeira, Funchal, Portugal, 23-26 June 2014}, abstract = {

The transition to cloud computing offers a large number of benefits, such as lower capital costs and a highly agile environment. Yet, the development of software engineering practices has not kept pace with this change. Moreover, the design and runtime behavior of cloud based services and the underlying cloud infrastructure are largely decoupled from one another.This paper describes the innovative concepts being developed by CloudWave to utilize the principles of DevOps to create an execution analytics cloud infrastructure where, through the use of programmable monitoring and online data abstraction, much more relevant information for the optimization of the ecosystem is obtained. Required optimizations are subsequently negotiated between the applications and the cloud infrastructure to obtain coordinated adaption of the ecosystem. Additionally, the project is developing the technology for a Feedback Driven Development Standard Development Kit which will utilize the data gathered through execution analytics to supply developers with a powerful mechanism to shorten application development cycles. {\textcopyright} 2014 IEEE.

}, keywords = {cloud computing, Cloud managements, Coordinated Adaptation, DevOps}, isbn = {9781479942770}, issn = {15301346}, doi = {10.1109/ISCC.2014.6912638}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84908149098\&partnerID=40\&md5=a0097ef370a848f29a660ea120514a63}, author = {Dario Bruneo and Thomas Fritz and Sharon Keidar-Barner and Philipp Leitner and Francesco Longo and Clarissa Marquezan and Andreas Metzger and Klaus Pohl and Antonio Puliafito and Danny Raz and Andreas Roth and Eliot Salant and Itai Segall and Massimo Villari and Yaron Wolfsthal and Chris Woods} } @proceedings {Bruneo201384, title = {Analytical evaluation of resource allocation policies in green IaaS clouds}, journal = {Proceedings of the IEEE 3rd International Conference on Cloud and Green Computing (CGC) Co-located with the IEEE 3rd International Conference on Social Computing and Its Applications (SCA)}, year = {2013}, note = {cited By 1; Conference of 3rd IEEE International Conference on Cloud and Green Computing, CGC 2013, Held Jointly with the 3rd IEEE International Conference on Social Computing and Its Applications, SCA 2013 ; Conference Date: 30 September 2013 Through 2 October 2013; Conference Code:102391}, pages = {84-91}, publisher = {IEEE Computer Society}, address = {Karlsruhe, Germany, 30 September - 2 October 2013}, abstract = {

Cloud systems represent the new ICT frontier where computing utilities are offered in terms of virtual instances, following the so called as-a-service philosophy. Different commercial solutions have been already put in place but several aspects need to be faced in order to provide high-value services able to meet business requirements. In particular, performance evaluation plays a critical role being strictly related to data center optimization and user satisfaction. Moreover, the use of large data centers able to respond to the high service demand has increased the attention to power efficiency, thus calling for green solutions and energy-aware strategies that jointly consider environmental and economical aspects. In order to design powerful strategies able to meet the quality of service requirements still reducing the energy costs, performance analysis frameworks are needed. In this paper, we present an analytical model, based on stochastic reward nets, that is able to easily implement resource allocation strategies in a green infrastructure as-a-service cloud. The model is organized into layers that represent the virtual resource pool and the physical machines. Different allocation algorithms (i.e., scattering, saturation) have been implemented by properly managing the coordination between the model layers. Numerical results are provided that demonstrate the effectiveness of the proposed approach. {\textcopyright} 2013 IEEE.

}, keywords = {Analytical evaluation, cloud computing, Distributed computer systems, Green Computing, Performance analysis, Performance evaluation, Quality of service, Resource allocation, Resource allocation policy, Resource allocation strategies, Service requirements, Stochastic reward nets, Stochastic systems}, isbn = {9780769551142}, doi = {10.1109/CGC.2013.21}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84893329592\&partnerID=40\&md5=369f37efc4aabea38300336d819db864}, author = {Dario Bruneo and Audric Lhoas and Francesco Longo and Antonio Puliafito} } @article {43, title = {Evaluating A File Fragmentation System For Multi-provider Cloud Storage}, journal = {SCALABLE COMPUTING. PRACTICE AND EXPERIENCE}, volume = {14}, year = {2013}, pages = {265{\textendash}277}, abstract = {

Currently, storage services represent a new way to do business in Cloud computing. This new trend is proved by the number of Cloud storage providers that are appearing on the market. In this work, we present an innovative approach useful for using different Cloud storage providers in a transparent way, avoiding both data lock-in and possible data privacy violation that can be caused by providers themselves. More specifically, we propose an approach enabling Cloud customers to rely on many Cloud storage providers. Differently from other solutions, with our approach only the customers have the full control of their data, and in addition, if a provider suddenly disappears and/or it is not available anymore, the customers will be able to continue accessing their data, reconstructing them from data fragments replicated in other Cloud storage providers. The paper shows how such an approach works. In particular, experiments, besides proving the goodness of our approach, also provide several guidelines regarding how to properly configure software systems in order to meet the customer{\textquoteright}s requirements (in terms of both QoS and costs).

}, keywords = {Big Data, cloud computing, Confidentiality., Reliability, Storage}, doi = {10.12694/scpe.v14i4.932}, url = {http://www.scpe.org/index.php/scpe/article/view/932/0}, author = {Massimo Villari and Antonio Celesti and Maria Fazio and Antonio Puliafito} } @article {42, title = {A Message Oriented Middleware for Cloud Computing To Improve Efficiency in Risk Management Systems}, journal = {SCALABLE COMPUTING. PRACTICE AND EXPERIENCE}, volume = {14}, year = {2013}, pages = {201{\textendash}213}, abstract = {

Transportation of Dangerous Goods represents a sensitive problem due its congenital high potential risk of causing disaster if an accident occurs. Transportation of Dangerous Goods Risk Management systems reduce the possibility of both accidental disasters and terrorist attacks detecting unusual events and blocking possible threats. Cloud computing can facilitate the development of such kinds of systems thanks to new emerging paradigms and technologies. In this paper, we discuss the design of a new Message-Oriented Cloud Middleware for Cloud, that can be used to develop a Cloud-based Transportation of Dangerous Goods Risk Management system. More specifically, we investigate issues on transportation of Dangerous Goods, in order to focus the attention on the requirements of the Risk Management system. Then, we describe how to use the Message-Oriented Cloud Middleware for Cloud architecture and the necessary utilities in particular here for supporting Transportation of Dangerous Goods.

}, keywords = {cloud computing, federation, message oriented middleware, planetary system model, service provisioning}, doi = {10.12694/scpe.v14i4.928}, url = {http://www.scpe.org/index.php/scpe/article/view/928/0}, author = {Maria Fazio and Antonio Celesti and Antonio Puliafito and Massimo Villari} } @inbook {54, title = {Towards Energy Sustainability in Federated and Interoperable Clouds}, booktitle = {Communication Infrastructures for Cloud Computing}, year = {2013}, pages = {329{\textendash}350}, publisher = {IGI Global Publisher}, organization = {IGI Global Publisher}, address = {Hershey, Pennsylvania, US}, abstract = {

Cloud federation is paving the way toward new business scenarios in which it is possible to enforce more flexible energy management strategies than in the past. Considering independent cloud providers, each one is exclusively bound to the specific energy supplier powering its datacenter. The situation radically changes if we consider a federation of cloud providers powered by both a conventional energy supplier and a renewable energy generator. In such a context, the opportune relocation of computational workload among providers can lead to a global energy sustainability policy for the whole federation. In this work, the authors investigate the advantages and issues for the achievement of such a sustainable environment.

}, keywords = {cloud computing, Energy Efficiency}, issn = {978-146664853-1;146664852X;978-146664852-4}, doi = {10.4018/978-1-4666-4522-6.ch015}, url = {http://www.igi-global.com/chapter/towards-energy-sustainability-in-federated-and-interoperable-clouds/82545}, author = {Antonio Celesti and Antonio Puliafito and Francesco Tusa and Massimo Villari} } @article {Bruneo20131072, title = {Workload-based software rejuvenation in cloud systems}, journal = {IEEE Transactions on Computers - IEEE Computer Society}, volume = {62}, number = {6}, year = {2013}, note = {cited By 21}, pages = {1072-1085}, abstract = {

Cloud computing is a promising paradigm able to rationalize the use of hardware resources by means of virtualization. Virtualization allows to instantiate one or more virtual machines (VMs) on top of a single physical machine managed by a virtual machine monitor (VMM). Similarly to any other software, a VMM experiences aging and failures. Software rejuvenation is a proactive fault management technique that involves terminating an application, cleaning up the system internal state, and restarting it to prevent the occurrence of future failures. In this work, we propose a technique to model and evaluate the VMM aging process and to investigate the optimal rejuvenation policy that maximizes the VMM availability under variable workload conditions. Starting from dynamic reliability theory and adopting symbolic algebraic techniques, we investigate and compare existing time-based VMM rejuvenation policies. We also propose a time-based policy that adapts the rejuvenation timer to the VMM workload condition improving the system availability. The effectiveness of the proposed modeling technique is demonstrated through a numerical example based on a case study taken from the literature. {\textcopyright} 1968-2012 IEEE.

}, keywords = {Algebraic techniques, Application programs, cloud computing, Endocrinology, Kronecker algebra, Numerical methods, phase type distributions, Proactive fault managements, Reliability theory, Software rejuvenation, System availability, Time-based Rejuvenation, Virtual machine monitors, Virtual reality}, issn = {00189340}, doi = {10.1109/TC.2013.30}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84877311601\&partnerID=40\&md5=185051c9b74e6577b5b06c39cbaf7cc7}, author = {Dario Bruneo and Salvatore Distefano and Francesco Longo and Antonio Puliafito and Marco Scarpa} } @proceedings {Bruneo2012277, title = {Modeling energy-aware cloud federations with SRNs}, journal = {32nd International Conference on Application and Theory of Petri Nets and Concurrency (Petri Nets)}, volume = {7400 Lecture Notes in Computer Science}, year = {2012}, note = {cited By 4; Conference of 32nd International Conference on Application and Theory of Petri Nets and Concurrency, Petri Nets 2011 ; Conference Date: 20 June 2011 Through 24 June 2011; Conference Code:94089}, pages = {277-307}, publisher = {Springer-Verlag}, address = {Newcastle upon Tyne, United Kingdom, 20-24 June 2011}, abstract = {

Cloud computing is a challenging technology that promises to strongly modify the way computing and storage resources will be accessed in the near future. However, it may demand huge amount of energy if adequate management policies are not put in place. In particular, in the context of Infrastructure as a Service (IaaS) Cloud, optimization strategies are needed in order to allocate, migrate, consolidate virtual machines, and manage the switch on/switch off period of a data centre. In this paper, we present a methodology based on stochastic reward nets (SRNs) to investigate the more convenient strategies to manage a federation of two or more private or public IaaS Clouds. Several policies are presented and their impact is evaluated, thus contributing to a rational and efficient adoption of the Cloud computing paradigm. {\textcopyright} 2012 Springer-Verlag.

}, keywords = {cloud computing, Computing paradigm, Data centres, Digital storage, Energy aware, Energy conservation, Management policy, Optimization strategy, Performance evaluation, Petri nets, Quality of service, Stochastic reward nets, Stochastic systems, Storage resources, Switch-on, virtual machines}, isbn = {9783642351785}, issn = {03029743}, doi = {10.1007/978-3-642-35179-2_12}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84870045120\&partnerID=40\&md5=b1e106331e417cc512bcbc713cc582de}, author = {Dario Bruneo and Francesco Longo and Antonio Puliafito} } @proceedings {Bruneo20128, title = {Software rejuvenation in the cloud}, journal = {Proceedings of the 5th International Conference on Simulation Tools and Techniques (SIMUTools)}, year = {2012}, note = {cited By 0; Conference of 5th International Conference on Simulation Tools and Techniques, SIMUTools 2012 ; Conference Date: 19 March 2012 Through 23 March 2012; Conference Code:110134}, pages = {8-16}, publisher = {ICST}, address = {Desenzano del Garda, Italy, 19-23 March 2012}, abstract = {

In this paper, we investigate how software rejuvenation can be used in a Cloud environment to increase the availability of a virtualized system composed of a single virtual machine monitor (VMM) on top of which a certain number of virtual machines (VMs) can be instantiated. We start from the assumption that the aging of a VMM increases with the number of VMs it is managing, thus characterizing the problem in terms of dynamic reliability. Therefore, by identifying the age of the VMM with its reliability and based on the conservation of reliability principle, we characterize the time to failure of the VMM through continuous phase type distributions. The system availability is thus modeled by an expanded continuous time Markov chain expressed in terms of Kronecker algebra in order to face the state space explosion and to keep memory of the age reached by the VMM in case the number of the hosted VMs change. Time-based rejuvenation is taken into consideration and the optimal timer is evaluated in order to maximize the VMM availability. Copyright {\textcopyright} 2012 ICST.

}, keywords = {Availability, cloud computing, Continuous phase type distributions, Continuous time Markov chain, Continuous time systems, Endocrinology, Java programming language, Markov processes, phase type distributions, Rejuvenation, Reliability, Reliability principles, Software rejuvenation, Virtual machine monitors, Virtual reality, Virtualized environment}, isbn = {9781450315104}, doi = {10.4108/icst.simutools.2012.247772}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84922767370\&partnerID=40\&md5=a03b06eec703c94d55c0f4875f181902}, author = {Dario Bruneo and Francesco Longo and Antonio Puliafito and Marco Scarpa and Salvatore Distefano} } @proceedings {Bruneo2011, title = {Evaluating energy consumption in a cloud infrastructure}, journal = {2011 IEEE International Symposium on a World of Wireless, Mobile and Multimedia Networks (WoWMoM)}, year = {2011}, note = {cited By 4; Conference of 2011 IEEE International Symposium on a World of Wireless, Mobile and Multimedia Networks, WoWMoM 2011 ; Conference Date: 20 June 2011 Through 23 June 2011; Conference Code:86401}, publisher = {IEEE Computer Society}, address = {Lucca, Italy, 20-23 June 2011}, abstract = {

Cloud computing is a challenging technology that promises to strongly modify the way computing and storage resources will be accessed in the near future. Clouds may demand huge amount of energy if adequate management policies are not put in place. Optimization strategies are needed in order to allocate, migrate, consolidate virtual machines and manage the switch on/switch off period of a data center. In this paper, we present a modeling approach based on Stochastic reward nets to investigate the more convenient strategies to manage a federation of Clouds, having in mind the final goal to reduce the overall energy consumption. Several policies are presented and their impact is evaluated, thus contributing to a rational and efficient adoption of the Cloud computing paradigm. {\textcopyright} 2011 IEEE.

}, keywords = {cloud computing, Clouds, computer systems, Computing paradigm, Data centers, Energy utilization, Management policy, Modeling approach, Multimedia systems, Optimization strategy, Performance evaluation, Quality control, Quality of service, Stochastic reward nets, Stochastic systems, Storage resources, Switch-on, virtual machines, Wireless networks}, isbn = {9781457703515}, doi = {10.1109/WoWMoM.2011.5986479}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-80052709389\&partnerID=40\&md5=9d12783598805d3b668813d0d5b70057}, author = {Dario Bruneo and Francesco Longo and Antonio Puliafito} } @proceedings {Ragusa200953, title = {Experiencing with the cloud over glite}, journal = {Proceedings of the 2009 ICSE Workshop on Software Engineering Challenges of Cloud Computing (CLOUD)}, year = {2009}, note = {cited By 7; Conference of 2009 ICSE Workshop on Software Engineering Challenges of Cloud Computing, CLOUD 2009 ; Conference Date: 23 May 2009 Through 23 May 2009; Conference Code:77503}, pages = {53-60}, publisher = {IEEE Computer Society}, address = {Vancouver, BC, Canada, 23 May 2009}, abstract = {

Market competitiveness puts enormous pressures over companies to be agile in providing their offers and adapt to fast changes. In such context, resource dimensioning is an hard and risky task which may lead companies to un-derprovision their data-center, and therefore be unable to cope with peak loads, or to overprovision it, and notfullfill their ROI. Cloud computing ought to provide such ability. In a previous work, we presented our solution for multi-tier web-based application hosting over a gLite based infrastructure. In this paper, we present a further development of our system towards the Cloud model. A scenario describing our system in action is also discussed. {\textcopyright} 2009 IEEE.

}, keywords = {cloud computing, Cloud models, Competition, Computer science, Computer software, Further development, Multi-tier, Peak load, Resource dimensioning, Web-based applications}, isbn = {9781424437139}, doi = {10.1109/CLOUD.2009.5071533}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-70349805168\&partnerID=40\&md5=623b9f32a7f837e0d594e9a3c0685b06}, author = {Carmelo Ragusa and Francesco Longo and Antonio Puliafito} }