TransCom: a virtual disk-based cloud computing platform for heterogeneous services

PublishedJournal ArticleThis paper presents the design, implementation, and evaluation of TransCom, a virtual disk (Vdisk) based cloud computing platform that supports heterogeneous services of operating systems (OSes) and their applications in enterprise environments. In TransCom, clients store all data and software, including OS and application software, on Vdisks that correspond to disk images located on centralized servers, while computing tasks are carried out by the clients. Users can choose to boot any client for using the desired OS, including Windows, and access software and data services from Vdisks as usual without consideration of any other tasks, such as installation, maintenance, and management. By centralizing storage yet distributing computing tasks, TransCom can greatly reduce the potential system maintenance and management costs. We have implemented a multi-platform TransCom prototype that supports both Windows and Linux services. The extensive evaluation based on both test-bed experiments and real-usage experiments has demonstrated that TransCom is a feasible, scalable, and efficient solution for successful real-world use. © 2004-2012 IEEE

Towards non-intrusive software introspection and beyond

Continuous verification and security analysis of software systems are of paramount importance to many organizations. The state-of-the-art for such operations implements agent-based approaches to inspect the provisioned software stack for security and compliance issues. However, this approach, which runs agents on the systems being analyzed, is vulnerable to some attacks, can incur substantial performance impact, and can introduce significant complexity. In this paper, we present the design and prototype implementation of a general-purpose approach for Non-intrusive Software Introspection (NSI). By adhering to NSI, organizations hosting in the cloud can as well control the software introspection workflow with reduced trust in the provider. Experimental analysis of real-world applications demonstrates that NSI presents a lightweight and scalable approach, and has a negligible impact on the performance of applications running on the instance being introspected.Accepted manuscrip

Replication and Caching Systems for the support of VMs stored in File Systems with Snapshots

Recently, in a relatively short timeframe, there were fundamental changes in the way computing power is used. Virtualisation technology has changed both the model of a data centre’s infrastructure and the way physical computers are now managed. This shift is a consequence of today’s fast deployment rate of Virtual Machines (VM) in a high consolidation environment with minimal need for human management. New approaches to virtualisation techniques are being developed at a surprisingly fast rate, leading to a new exciting and vibrating ecosystem of platforms and services. We see the big industry players tackling problems such as Desktop Virtualisation with moderate success, but completely ignoring the computation power already present in their clients’ infrastructures and, instead, opting for a costly solution based on powerful new machines. There’s still room for improvement in Virtual Desktop Infrastructure (VDI) and development of new architectures that take advantage of the computation power available at the user’s desk, with a minimum effort on the management side; Infrastructure for Client-Based Desktops (iCBD) is one of these projects. This thesis focuses on the development of mechanisms for the replication and caching of VM images stored in a local filesystem, albeit one with the ability to perform snapshots. In this work, there are some challenges to address: the proposed architecture must be entirely distributed and completely integrated with the already existing client-based VDI platform; and it must be able to efficiently cope with very large, read-only files, (some of them snapshots) and handle their multiple versions. This work will also explore the challenges and advantages of deploying such a system in a high throughput network, with both high availability and scalability while efficiently supporting a large number of users (and their workstations)

Automatsko proširenje i primjena računalnog grozda korištenjem dual-boot principa

The paper presents an innovative and simple way of creating computer clustering and obtaining HPC clusters using computers in the classroom, Ethernet facilities and open source software. Automatic enlarge of a computer cluster is a cost-effective way to increase available computing power. This is achieved by forming a computer cluster from the computers in the classroom. The main aim of this paper is to present a solution that will use existing resources in the computer classroom, for applying complex computer services/jobs under the Linux operating system. The execution of these services/jobs programs is performed at the time when the computing resources are not in used in learning under the Windows operating system. A real-life example of applying computers in dual-boot Windows/Linux work mode along with the developed software application support is presented in a teaching environment. The implementation also includes logistics and support for automatic computer clustering and for service/job programs execution. The primary goal is to use existing resources for useful applications in education in the image programming, simulations and volume rendering.U radu je prikazan inovativan i jednostavan način stvaranja računalnih klastera i dobivanja HPC klastera korištenjem postojećih računala u učionici, Ethernet objekata, i open source softvera. Automatsko oblikovanje računalnog klastera je ekonomičan način da se poveća raspoloživa računalna snaga. To se postiže formiranjem računalnog klastera od postojećih računala u učionici. Glavni cilj ovog rada je prikazati rješenje koja će koristiti postojeće resurse u okruženju računalne učionice za izvođenje složenih računalnih poslova koji zahtjevaju vec´u računalnu snagu pod Linux operativnim sustavom. Izvršenje tih poslova se obavlja u vrijeme kada se računalni resursi ne koriste za obrazovanje pod Windows operativnim sustavom. Prikazan je primjer primjene računala u dual-boot Windows/Linux modu rada uz razvijene originalne programske podrške za aplikacije u obrazovnom okruženju. Provedba također uključuje logistiku i podršku za automatsko klasteriranje računala i izvršavanje poslova. Primarni cilj je iskorištavanje postojećih resursa za korisne aplikacije u obrazovanju primarno u području programiranja slike, simulacije i renderiranja. Rezultati provedenog principa su prikazani

Integração de funções de rede virtualizadas e funções de rede físicas

Network Functions Virtualization (NFV) and Software Defined Networking (SDN) have been in the center of network evolution, promising a more flexible and efficient way of managing networks through the on-demand instantiation of network functions (NFs) and reconfigurability of the network as necessary. Nevertheless, as new mechanisms are developed, such technologies require testing before their adoption into real-world deployments. This is where this dissertation contributes, by proposing and evaluating a system architecture that integrates a physical wireless testbed with a cloud-based environment. This allows physical wireless nodes to become part of the cloud environment, enabling its use and configuration as virtual NFs (VNFs). Results showcased the system feasibility, with the testbed being able to instantiate on-demand virtual and physical NFs, in the physical wireless nodes and in an OpenStack data-center.A Virtualização de Funções de Rede e as Redes Definidas por Software têm estado no centro da evolução das redes, prometendo uma forma mais flexível e eficiente de as gerenciar através da instanciação on-demand de Funções de Rede e da sua reconfiguração conforme o necessário. No entanto, à medida que novos mecanismos são desenvolvidos, é também necessário a realização de testes sobre estas tecnologias antes destas serem adotadas em implementações em contexto real. É aqui que esta dissertação contribui, propondo e avaliando uma arquitetura de sistema que integra um testbed físico sem fios, com um ambiente baseado em nuvem. Isto permite que os nós sem fios físicos se tornem parte do ambiente de nuvem, permitindo o seu uso e configuração como Funções de Rede Virtuais. Os resultados demonstraram a viabilidade do sistema, dada a capacidade da testbed em instanciar Funções de Rede virtuais e físicas quando requisitadas tanto nos nós sem fios físicos quanto no servidor OpenStack.Mestrado em Engenharia Eletrónica e Telecomunicaçõe

Kadeploy3: Efficient and Scalable Operating System Provisioning for HPC Clusters

Operating system provisioning is a common and critical task in cluster computing environments. The required low-level operations involved in provisioning can drastically decrease the performance of a given solution, and maintaining a reasonable provisioning time on clusters of 1000+ nodes is a significant challenge. We present Kadeploy3, a tool built to efficiently and reliably deploy a large number of cluster nodes. Since it is a keystone of the Grid'5000 experimental testbed, it has been designed not only to help system administrators install and manage clusters but also to provide testbed users with a flexible way to deploy their own operating systems on nodes for their own experimentation needs, on a very frequent basis. In this paper we detail the design principles of Kadeploy3 and its main features, and evaluate its capabilities in several contexts. We also share the lessons we have learned during the design and deployment of Kadeploy3 in the hope that this will help system administrators and developers of similar solutions

Xen Worlds: Creating a virtual laboratory environment for use in education

The Xen Worlds project uses the Xen hypervisor to create a virtual lab environment, providing students with personal networks of fully functional virtual machines (VMs) called a Xen World. The Xen Worlds environment can be provided using minimal hardware, and uses open source software, making it a low-cost option for education. The current hardware, consisting of five modest servers is capable of providing 470 VMs. Since each Xen World can be isolated from each other, and from the Internet, students can be provided root access to their VMs without the security and privacy issues that would be present in a normal shared lab. In addition, to support off-campus students, Xen Worlds has several features that ensure the system is equally accessible and easy to use, even if the student has limited access to computing or network resources. To rate the usability and effectiveness of the Xen Worlds environment, student feedback was collected through the use of surveys. The results indicate students feel the environment is an enjoyable and effective teaching method, with comments indicating a desire for a greater number of assignments to be provided

Commodity single board computer clusters and their applications

© 2018 Current commodity Single Board Computers (SBCs) are sufficiently powerful to run mainstream operating systems and workloads. Many of these boards may be linked together, to create small, low-cost clusters that replicate some features of large data center clusters. The Raspberry Pi Foundation produces a series of SBCs with a price/performance ratio that makes SBC clusters viable, perhaps even expendable. These clusters are an enabler for Edge/Fog Compute, where processing is pushed out towards data sources, reducing bandwidth requirements and decentralizing the architecture. In this paper we investigate use cases driving the growth of SBC clusters, we examine the trends in future hardware developments, and discuss the potential of SBC clusters as a disruptive technology. Compared to traditional clusters, SBC clusters have a reduced footprint, are low-cost, and have low power requirements. This enables different models of deployment—particularly outside traditional data center environments. We discuss the applicability of existing software and management infrastructure to support exotic deployment scenarios and anticipate the next generation of SBC. We conclude that the SBC cluster is a new and distinct computational deployment paradigm, which is applicable to a wider range of scenarios than current clusters. It facilitates Internet of Things and Smart City systems and is potentially a game changer in pushing application logic out towards the network edge

Evolving an efficient and effective off-the-shelf computing infrastructure for schools in rural areas of South Africa

Upliftment of rural areas and poverty alleviation are priorities for development in South Africa. Information and knowledge are key strategic resources for social and economic development and ICTs act as tools to support them, enabling innovative and more cost effective approaches. In order for ICT interventions to be possible, infrastructure has to be deployed. For the deployment to be effective and sustainable, the local community needs to be involved in shaping and supporting it. This study describes the technical work done in the Siyakhula Living Lab (SLL), a long-term ICT4D experiment in the Mbashe Municipality, with a focus on the deployment of ICT infrastructure in schools, for teaching and learning but also for use by the communities surrounding the schools. As a result of this work, computing infrastructure was deployed, in various phases, in 17 schools in the area and a “broadband island” connecting them was created. The dissertation reports on the initial deployment phases, discussing theoretical underpinnings and policies for using technology in education as well various computing and networking technologies and associated policies available and appropriate for use in rural South African schools. This information forms the backdrop of a survey conducted with teachers from six schools in the SLL, together with experimental work towards the provision of an evolved, efficient and effective off-the-shelf computing infrastructure in selected schools, in order to attempt to address the shortcomings of the computing infrastructure deployed initially in the SLL. The result of the study is the proposal of an evolved computing infrastructure model for use in rural South African schools

High availability using virtualization

High availability has always been one of the main problems for a data center. Till now high availability was achieved by host per host redundancy, a highly expensive method in terms of hardware and human costs. A new approach to the problem can be offered by virtualization. Using virtualization, it is possible to achieve a redundancy system for all the services running on a data center. This new approach to high availability allows to share the running virtual machines over the servers up and running, by exploiting the features of the virtualization layer: start, stop and move virtual machines between physical hosts. The system (3RC) is based on a finite state machine with hysteresis, providing the possibility to restart each virtual machine over any physical host, or reinstall it from scratch. A complete infrastructure has been developed to install operating system and middleware in a few minutes. To virtualize the main servers of a data center, a new procedure has been developed to migrate physical to virtual hosts. The whole Grid data center SNS-PISA is running at the moment in virtual environment under the high availability system. As extension of the 3RC architecture, several storage solutions have been tested to store and centralize all the virtual disks, from NAS to SAN, to grant data safety and access from everywhere. Exploiting virtualization and ability to automatically reinstall a host, we provide a sort of host on-demand, where the action on a virtual machine is performed only when a disaster occurs.Comment: PhD Thesis in Information Technology Engineering: Electronics, Computer Science, Telecommunications, pp. 94, University of Pisa [Italy