The Experts below are selected from a list of 10485 Experts worldwide ranked by ideXlab platform

Felix Freitag - One of the best experts on this subject based on the ideXlab platform.

  • a lightweight service placement approach for Community Network micro clouds
    Journal of Grid Computing, 2019
    Co-Authors: Mennan Selimi, Arjuna Sathiaseelan, Felix Freitag, Luís Veiga, Llorenc Cerdaalabern, Jon Crowcroft
    Abstract:

    Community Networks (CNs) have gained momentum in the last few years with the increasing number of spontaneously deployed WiFi hotspots and home Networks. These Networks, owned and managed by volunteers, offer various services to their members and to the public. While Internet access is the most popular service, the provision of services of local interest within the Network is enabled by the emerging technology of CN micro-clouds. By putting services closer to users, micro-clouds pursue not only a better service performance, but also a low entry barrier for the deployment of mainstream Internet services within the CN. Unfortunately, the provisioning of these services is not so simple. Due to the large and irregular topology, high software and hardware diversity of CNs, a “careful” placement of micro-clouds services over the Network is required to optimize service performance. This paper proposes to leverage state information about the Network to inform service placement decisions, and to do so through a fast heuristic algorithm, which is critical to quickly react to changing conditions. To evaluate its performance, we compare our heuristic with one based on random placement in Guifi.net, the biggest CN worldwide. Our experimental results show that our heuristic consistently outperforms random placement by 2x in bandwidth gain. We quantify the benefits of our heuristic on a real live video-streaming service, and demonstrate that video chunk losses decrease significantly, attaining a 37% decrease in the packet loss rate. Further, using a popular Web 2.0 service, we demonstrate that the client response times decrease up to an order of magnitude when using our heuristic. Since these improvements translate in the QoE (Quality of Experience) perceived by the user, our results are relevant for contributing to higher QoE, a crucial parameter for using services from volunteer-based systems and adapting CN micro-clouds as an eco-system for service deployment.

  • Gossip-based service monitoring platform for wireless edge cloud computing
    2017 IEEE 14th International Conference on Networking Sensing and Control (ICNSC), 2017
    Co-Authors: Nuno Apolónia, Leandro Navarro, Felix Freitag, Sarunas Girdzijauskas, Vladimir Vlassov
    Abstract:

    Edge cloud computing proposes to support shared services, by using the infrastructure at the Network's edge. An important problem is the monitoring and management of services across the edge environment. Therefore, dissemination and gathering of data is not straightforward, differing from the classic cloud infrastructure. In this paper, we consider the environment of Community Networks for edge cloud computing, in which the monitoring of cloud services is required. We propose a monitoring platform to collect near real-time data about the services offered in the Community Network using a gossip-enabled Network. We analyze and apply this gossip-enabled Network to perform service discovery and information sharing, enabling data dissemination among the Community. We implemented our solution as a prototype and used it for collecting service monitoring data from the real operational Community Network cloud, as a feasible deployment of our solution. By means of emulation and simulation we analyze in different scenarios, the behavior of the gossip overlay solution, and obtain average results regarding information propagation and consistency needs, i.e. in high latency situations, data convergence occurs within minutes.

  • GECON - Towards incentive-compatible pricing for bandwidth reservation in Community Network clouds
    Economics of Grids Clouds Systems and Services, 2016
    Co-Authors: Amin M Khan, Xavier Vilaça, Luís Rodrigues, Felix Freitag
    Abstract:

    Community Network clouds provide for applications of local interest deployed within Community Networks through collaborative efforts to provision cloud infrastructures. They complement the traditional large-scale public cloud providers similar to the model of decentralised edge clouds by bringing both content and computation closer to the users at the edges of the Network. Services and applications within Community Network clouds require connectivity to the Internet and to the resources external to the Community Network, and here the current best-effort model of volunteers contributing gateway access in the Community Networks falls short. We model the problem of reserving the bandwidth at such gateways for guaranteeing quality-of-service for the cloud applications, and evaluate different pricing mechanisms for their suitability in ensuring maximal social welfare and eliciting truthful requests from the users. We find second-price auction based mechanisms, including Vickrey and generalised second price auctions, suitable for the bandwidth allocation problem at the gateways in the Community Networks.

  • Energy Efficient Cloud Service Provisioning: Keeping Data Center Granularity in Perspective
    Journal of Grid Computing, 2016
    Co-Authors: Leila Sharifi, Felix Freitag, Llorenc Cerda-alabern, Luís Veiga
    Abstract:

    The cost of power and its associated delivery are becoming significant factors in the total expenditure of large-scale data centers. Numerous techniques have been proposed to address the energy efficiency issue in cloud systems. Recently, some efforts have been made to decentralize the cloud via distributing data centers in diverse geographical positions, at different scales. In this paper, we elaborate on the energy effectiveness of service provisioning on different cloud architectures, from a mega-data center to a nano data center, which provides the extreme decentralization in terms of cloud architecture, as well as P2P-clouds or Community Network clouds. We study the energy consumption through an analytical and simulation framework for video streaming and MapReduce applications.

  • Bandwidth-Aware Service Placement in Community Network Micro-Clouds
    2016 IEEE 41st Conference on Local Computer Networks (LCN), 2016
    Co-Authors: Mennan Selimi, Arjuna Sathiaseelan, Llorenc Cerda-alabern, Luís Veiga, Liang Wang, Felix Freitag
    Abstract:

    Seamless computing and service sharing in Community Networks (CNs) have gained momentum due to the emerging technology of Community Network micro-clouds (CNMCs). However, deploying and running services in CNMCs confront enormous challenges to cope with, such as the dynamic nature of micro-clouds, limited capacity of nodes and links, asymmetric quality of wireless links, geographic singularity based deployment model rather than Network QoS based, etc. CNMCs have been increasingly used by Network-intensive services which exchange significant amounts of data between nodes, therefore their performance heavily relies on the available bandwidth resource in a Network. This paper proposes a novel bandwidth-aware service placement algorithm which aims to replace the current random placement adopted by Guifi.net. Our experimental results show that the proposed BASP algorithm consistently outperforms the random placement in Guifi.net by 35% regarding its bandwidth gain. More promisingly, as the number of services increases, the gain tends to increase accordingly.

John F Patterson - One of the best experts on this subject based on the ideXlab platform.

  • stimulating social engagement in a Community Network
    Conference on Computer Supported Cooperative Work, 2002
    Co-Authors: David R Millen, John F Patterson
    Abstract:

    One of the most challenging problems facing builders and facilitators of Community Networks is to create and sustain social engagement among members. In this paper, we investigate the drivers of social engagement in a Community Network through the analysis of three data sources: activity logs, a member survey, and the content analysis of the conversation archives. We describe three important ways to encourage and support social engagement in online communities: through system design elements such as conversation channeling and event notification, by various selection criteria for Community members, and through facilitation of specific kinds of discussion topics.

  • CSCW - Stimulating social engagement in a Community Network
    Proceedings of the 2002 ACM conference on Computer supported cooperative work - CSCW '02, 2002
    Co-Authors: David R Millen, John F Patterson
    Abstract:

    One of the most challenging problems facing builders and facilitators of Community Networks is to create and sustain social engagement among members. In this paper, we investigate the drivers of social engagement in a Community Network through the analysis of three data sources: activity logs, a member survey, and the content analysis of the conversation archives. We describe three important ways to encourage and support social engagement in online communities: through system design elements such as conversation channeling and event notification, by various selection criteria for Community members, and through facilitation of specific kinds of discussion topics.

David R Millen - One of the best experts on this subject based on the ideXlab platform.

  • stimulating social engagement in a Community Network
    Conference on Computer Supported Cooperative Work, 2002
    Co-Authors: David R Millen, John F Patterson
    Abstract:

    One of the most challenging problems facing builders and facilitators of Community Networks is to create and sustain social engagement among members. In this paper, we investigate the drivers of social engagement in a Community Network through the analysis of three data sources: activity logs, a member survey, and the content analysis of the conversation archives. We describe three important ways to encourage and support social engagement in online communities: through system design elements such as conversation channeling and event notification, by various selection criteria for Community members, and through facilitation of specific kinds of discussion topics.

  • CSCW - Stimulating social engagement in a Community Network
    Proceedings of the 2002 ACM conference on Computer supported cooperative work - CSCW '02, 2002
    Co-Authors: David R Millen, John F Patterson
    Abstract:

    One of the most challenging problems facing builders and facilitators of Community Networks is to create and sustain social engagement among members. In this paper, we investigate the drivers of social engagement in a Community Network through the analysis of three data sources: activity logs, a member survey, and the content analysis of the conversation archives. We describe three important ways to encourage and support social engagement in online communities: through system design elements such as conversation channeling and event notification, by various selection criteria for Community members, and through facilitation of specific kinds of discussion topics.

Leandro Navarro - One of the best experts on this subject based on the ideXlab platform.

  • Gossip-based service monitoring platform for wireless edge cloud computing
    2017 IEEE 14th International Conference on Networking Sensing and Control (ICNSC), 2017
    Co-Authors: Nuno Apolónia, Leandro Navarro, Felix Freitag, Sarunas Girdzijauskas, Vladimir Vlassov
    Abstract:

    Edge cloud computing proposes to support shared services, by using the infrastructure at the Network's edge. An important problem is the monitoring and management of services across the edge environment. Therefore, dissemination and gathering of data is not straightforward, differing from the classic cloud infrastructure. In this paper, we consider the environment of Community Networks for edge cloud computing, in which the monitoring of cloud services is required. We propose a monitoring platform to collect near real-time data about the services offered in the Community Network using a gossip-enabled Network. We analyze and apply this gossip-enabled Network to perform service discovery and information sharing, enabling data dissemination among the Community. We implemented our solution as a prototype and used it for collecting service monitoring data from the real operational Community Network cloud, as a feasible deployment of our solution. By means of emulation and simulation we analyze in different scenarios, the behavior of the gossip overlay solution, and obtain average results regarding information propagation and consistency needs, i.e. in high latency situations, data convergence occurs within minutes.

  • IM - Deploying clouds in the Guifi Community Network
    2015 IFIP IEEE International Symposium on Integrated Network Management (IM), 2015
    Co-Authors: Roger Baig, Roc Meseguer, Felix Freitag, Pau Escrich, Leandro Navarro, Ermanno Pietrosemoli, Jim Dowling, Agusti Moll, Roger Pueyo, Vladimir Vlassov
    Abstract:

    This paper describes an operational geographically distributed and heterogeneous cloud infrastructure with services and applications deployed in the Guifi Community Network. The presented cloud is a particular case of a Community cloud, developed according to the specific needs and conditions of Community Networks. We describe the concept of this Community cloud, explain our technical choices for building it, and our experience with the deployment of this cloud. We review our solutions and experience on offering the different service models of cloud computing (IaaS, PaaS and SaaS) in Community Networks. The deployed cloud infrastructure aims to provide stable and attractive cloud services in order to encourage Community Network user to use, keep and extend it with new services and applications.

  • IM - The cloudy distribution in Community Network clouds in Guifi.net
    2015 IFIP IEEE International Symposium on Integrated Network Management (IM), 2015
    Co-Authors: Roger Baig, Felix Freitag, Pau Escrich, Leandro Navarro, Ermanno Pietrosemoli, Agusti Moll, Roger Pueyo, Rodrigo J. Carbajales, Jorge L. Florit, Mennan Selimi
    Abstract:

    This demo paper presents Cloudy, a Debian-based distribution to build and deploy clouds in Community Networks. The demonstration covers the following aspects: Installation of Cloudy, the Cloudy GUI for usage and administration by end users, demonstration of Cloudy nodes and services deployed in the Guifi Community Network.

  • IC2E - Deploying PaaS for Accelerating Cloud Uptake in the Guifi Community Network
    2014 IEEE International Conference on Cloud Engineering, 2014
    Co-Authors: Javi Jiménez, Felix Freitag, Pau Escrich, Roger Baig, Leandro Navarro
    Abstract:

    Community Networks is an emerging model in which communities of citizens build and own open shared Networks. But currently, cloud computing infrastructures, common in today's Internet, hardy exist in Community Networks. We present in this paper our approach for bringing clouds into Community Networks. The main element of our strategy for achieving cloud uptake is the deployment of the Guifi-Community-Distribution (GCODIS) on all cloud nodes, a distribution containing common services and applications. We argue in the paper the reasons why this approach is appropriate for the scenario of Community Networks, where the user acceptance needs to be gained. We show the steps and the on-going process with which we actually implement our approach in the Guifi Community Network. With these key elements in place, we conclude that we are closer to the vision that the users of Community Networks ultimately will not need to consume cloud applications from the Internet, but find them within the Community Network. An interesting open issue is to what extend our approach can be applied to the more generic volunteer computing scenario.

  • GIIS - Supporting cloud deployment in the Guifi.net Community Network
    Global Information Infrastructure Symposium - GIIS 2013, 2013
    Co-Authors: Javi Jiménez, Amir H. Payberah, Amin M Khan, Felix Freitag, Pau Escrich, Roger Baig, Marco Zennaro, Leandro Navarro, Ermanno Pietrosemoli, Vladimir Vlassov
    Abstract:

    Community Networking is an emerging model of a shared communication infrastructure in which communities of citizens build and own open Networks. Community Networks offer successfully IP-based Networking to the user. Cloud computing infrastructures however, while common in today's Internet, hardy exist in Community Networks. We explain our approach to bring clouds into the Guifi.net Community Network. For this we have started integrating part of our cloud prototype into the Guifi.net Community Network management tools. A proof-of-concept cloud infrastructure is currently under deployment in the Guifi.net Community Network. Our long term vision is that the users of Community Networks will not need to consume cloud applications from the Internet, but find them within the Community Network.

Vladimir Vlassov - One of the best experts on this subject based on the ideXlab platform.

  • Gossip-based service monitoring platform for wireless edge cloud computing
    2017 IEEE 14th International Conference on Networking Sensing and Control (ICNSC), 2017
    Co-Authors: Nuno Apolónia, Leandro Navarro, Felix Freitag, Sarunas Girdzijauskas, Vladimir Vlassov
    Abstract:

    Edge cloud computing proposes to support shared services, by using the infrastructure at the Network's edge. An important problem is the monitoring and management of services across the edge environment. Therefore, dissemination and gathering of data is not straightforward, differing from the classic cloud infrastructure. In this paper, we consider the environment of Community Networks for edge cloud computing, in which the monitoring of cloud services is required. We propose a monitoring platform to collect near real-time data about the services offered in the Community Network using a gossip-enabled Network. We analyze and apply this gossip-enabled Network to perform service discovery and information sharing, enabling data dissemination among the Community. We implemented our solution as a prototype and used it for collecting service monitoring data from the real operational Community Network cloud, as a feasible deployment of our solution. By means of emulation and simulation we analyze in different scenarios, the behavior of the gossip overlay solution, and obtain average results regarding information propagation and consistency needs, i.e. in high latency situations, data convergence occurs within minutes.

  • FiCloud - Stream Processing in Community Network Clouds
    2015 3rd International Conference on Future Internet of Things and Cloud, 2015
    Co-Authors: Ken Danniswara, Hooman Peiro Sajjad, Ahmad Al-shishtawy, Vladimir Vlassov
    Abstract:

    Community Network Cloud is an emerging distributed cloud infrastructure that is built on top of a Community Network. The infrastructure consists of a number of geographically distributed compute and storage resources, contributed by Community members, that are linked together through the Community Network. Stream processing is an important enabling technology that, if provided in a Community Network Cloud, would enable a new class of applications, such as social analysis, anomaly detection, and smart home power management. However, modern stream processing engines are designed to be used inside a data center, where servers communicate over a fast and reliable Network. In this work, we evaluate the Apache Storm stream processing framework in an emulated Community Network Cloud in order to identify the challenges and bottlenecks that exist in the current implementation. The Community Network emulation was performed using data collected from the Guifi.net Community Network, Spain. Our evaluation results show that, with proper configuration of the heartbeats, it is possible to run Apache Storm in a Community Network Cloud. The performance is sensitive to the placement of the Storm components in the Network. The deployment of management components on well-connected nodes improves the Storm topology scheduling time, fault tolerance, and recovery time. Our evaluation also indicates that the Storm scheduler and the stream groupings need to be aware of the Network topology and location of stream sources in order to optimally place Storm spouts and bolts to improve performance.

  • IM - Deploying clouds in the Guifi Community Network
    2015 IFIP IEEE International Symposium on Integrated Network Management (IM), 2015
    Co-Authors: Roger Baig, Roc Meseguer, Felix Freitag, Pau Escrich, Leandro Navarro, Ermanno Pietrosemoli, Jim Dowling, Agusti Moll, Roger Pueyo, Vladimir Vlassov
    Abstract:

    This paper describes an operational geographically distributed and heterogeneous cloud infrastructure with services and applications deployed in the Guifi Community Network. The presented cloud is a particular case of a Community cloud, developed according to the specific needs and conditions of Community Networks. We describe the concept of this Community cloud, explain our technical choices for building it, and our experience with the deployment of this cloud. We review our solutions and experience on offering the different service models of cloud computing (IaaS, PaaS and SaaS) in Community Networks. The deployed cloud infrastructure aims to provide stable and attractive cloud services in order to encourage Community Network user to use, keep and extend it with new services and applications.

  • Stream Processing in Community Network Clouds
    Proceedings - 2015 International Conference on Future Internet of Things and Cloud FiCloud 2015 and 2015 International Conference on Open and Big Data, 2015
    Co-Authors: Ken Danniswara, Hooman Peiro Sajjad, Ahmad Al-shishtawy, Vladimir Vlassov
    Abstract:

    Community Network Cloud is an emerging distributed cloud infrastructure\nthat is built on top of a Community Network. The infrastructure consists\nof a number of geographically distributed compute and storage resources,\ncontributed by Community members, that are linked together through the\nCommunity Network. Stream processing is an important enabling technology\nthat, if provided in a Community Network Cloud, would enable a new class\nof applications, such as social analysis, anomaly detection, and smart\nhome power management. However, modern stream processing engines are\ndesigned to be used inside a data center, where servers communicate over\na fast and reliable Network. In this work, we evaluate the Apache Storm\nstream processing framework in an emulated Community Network Cloud in\norder to identify the challenges and bottlenecks that exist in the\ncurrent implementation. The Community Network emulation was performed\nusing data collected from the Guifi.net Community Network, Spain. Our\nevaluation results show that, with proper configuration of the\nheartbeats, it is possible to run Apache Storm in a Community Network\nCloud. The performance is sensitive to the placement of the Storm\ncomponents in the Network. The deployment of management components on\nwell-connected nodes improves the Storm topology scheduling time, fault\ntolerance, and recovery time. Our evaluation also indicates that the\nStorm scheduler and the stream groupings need to be aware of the Network\ntopology and location of stream sources in order to optimally place\nStorm spouts and bolts to improve performance.

  • GIIS - Supporting cloud deployment in the Guifi.net Community Network
    Global Information Infrastructure Symposium - GIIS 2013, 2013
    Co-Authors: Javi Jiménez, Amir H. Payberah, Amin M Khan, Felix Freitag, Pau Escrich, Roger Baig, Marco Zennaro, Leandro Navarro, Ermanno Pietrosemoli, Vladimir Vlassov
    Abstract:

    Community Networking is an emerging model of a shared communication infrastructure in which communities of citizens build and own open Networks. Community Networks offer successfully IP-based Networking to the user. Cloud computing infrastructures however, while common in today's Internet, hardy exist in Community Networks. We explain our approach to bring clouds into the Guifi.net Community Network. For this we have started integrating part of our cloud prototype into the Guifi.net Community Network management tools. A proof-of-concept cloud infrastructure is currently under deployment in the Guifi.net Community Network. Our long term vision is that the users of Community Networks will not need to consume cloud applications from the Internet, but find them within the Community Network.