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Marco Aurelio Medina De Oliveira - One of the best experts on this subject based on the ideXlab platform.

  • Um repositorio de objetos para um ambiente de programação distribuida
    [s.n.], 2018
    Co-Authors: Marco Aurelio Medina De Oliveira
    Abstract:

    Orientador: Luiz Eduardo BuzatoDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de ComputaçãoResumo: O objetivo desta dissertação é a otimização do mecanismo de persistência do estado de objetos em um sistema de programação distribuída baseado em ações atômicas chamado Arjuna. O mecanismo atual de persistência em Arjuna tem um desempenho insatisfatório em termos de velocidade. Isto deve-se a utilização do sistema de arquivos hospedeiro (Unix) como repositório de objetos de forma inadequada. A provisão de ações atômicas é obtida através da técnica de cópias shadow sobre o repositório de objetos. A construção do repositório de objetos Hiper Store (High Performance Store) otimiza a persistência através da utilização de mecanismos de 10g e gerência de memória. Estes mecanismos já são utilizados em outros tipos de aplicações que suportam ações atômicas, como bancos de dados, e mostram-se eficientes também em Arjuna.Abstract: The purpose of this dissertation is the optimization of the object state persistence me­chanisms in a distributed programming System based on atomic actions called Arjuna. At this moment, the persistence mechanism in Arjuna has not a satisfactory performance about speed. This is due the utilization of Host File System (Unix) as object store in an inefficient way. Arjuna obtains atomic action support using the shadow copies technique over his object store. The Hiper Store (High Performance Store) implementation optimizes the persistence using mechanisms like log and memory manager. This mechanisms are also used in other applications that support atomic actions, like databases, and has also a good performance in Arjuna.MestradoMestre em Ciência da Computaçã

  • Um repositorio de objetos para um ambiente de programação distribuida
    2017
    Co-Authors: Marco Aurelio Medina De Oliveira
    Abstract:

    Resumo: O objetivo desta dissertação é a otimização do mecanismo de persistência do estado de objetos em um sistema de programação distribuída baseado em ações atômicas chamado Arjuna. O mecanismo atual de persistência em Arjuna tem um desempenho insatisfatório em termos de velocidade. Isto deve-se a utilização do sistema de arquivos hospedeiro (Unix) como repositório de objetos de forma inadequada. A provisão de ações atômicas é obtida através da técnica de cópias shadow sobre o repositório de objetos. A construção do repositório de objetos Hiper Store (High Performance Store) otimiza a persistência através da utilização de mecanismos de 10g e gerência de memória. Estes mecanismos já são utilizados em outros tipos de aplicações que suportam ações atômicas, como bancos de dados, e mostram-se eficientes também em ArjunaAbstract: The purpose of this dissertation is the optimization of the object state persistence me­chanisms in a distributed programming System based on atomic actions called Arjuna. At this moment, the persistence mechanism in Arjuna has not a satisfactory performance about speed. This is due the utilization of Host File System (Unix) as object store in an inefficient way. Arjuna obtains atomic action support using the shadow copies technique over his object store. The Hiper Store (High Performance Store) implementation optimizes the persistence using mechanisms like log and memory manager. This mechanisms are also used in other applications that support atomic actions, like databases, and has also a good performance in Arjun

Chunqiang Tang - One of the best experts on this subject based on the ideXlab platform.

  • FVD: a High-Performance Virtual Machine Image Format for Cloud. This is the longer version of the USENIX’11 paper with the same title, available at https://researcher.ibm.com/ researcher/view project.php?id=1852
    2013
    Co-Authors: Chunqiang Tang
    Abstract:

    Fast Virtual Disk (FVD) is a new virtual machine (VM) image format and the corresponding block device driver developed for QEMU. QEMU does I/O emulation for multiple hypervisors, including KVM, Xen-HVM, and VirtualBox. FVD is a holistic solution for both Cloud and non-Cloud environments. Its feature set includes flexible configurability, storage thin provisioning without a Host File System, compact image, internal snapshot, encryption, copy-on-write, copy-on-read, and adaptive prefetching. The last two features enable instant VM creation and instant VM migration, even if the VM image is stored on direct-attached storage. As its name indicates, FVD is fast. Experiments show that the throughput of FVD is 249 % higher than that of QCOW2 when using the Post-Mark benchmark to create Files.

  • fvd a high performance virtual machine image format for cloud
    USENIX Annual Technical Conference, 2011
    Co-Authors: Chunqiang Tang
    Abstract:

    Fast Virtual Disk (FVD) is a new virtual machine (VM) image format and the corresponding block device driver developed for QEMU. QEMU does I/O emulation for multiple hypervisors, including KVM, Xen-HVM, and VirtualBox. FVD is a holistic solution for both Cloud and non-Cloud environments. Its feature set includes flexible configurability, storage thin provisioning without a Host File System, compact image, internal snapshot, encryption, copy-on-write, copy-on-read, and adaptive prefetching. The last two features enable instant VM creation and instant VM migration, even if the VM image is stored on direct-attached storage. As its name indicates, FVD is fast. Experiments show that the throughput of FVD is 249% higher than that of QCOW2 when using the Post-Mark benchmark to create Files.

  • USENIX Annual Technical Conference - FVD: a high-performance virtual machine image format for cloud
    2011
    Co-Authors: Chunqiang Tang
    Abstract:

    Fast Virtual Disk (FVD) is a new virtual machine (VM) image format and the corresponding block device driver developed for QEMU. QEMU does I/O emulation for multiple hypervisors, including KVM, Xen-HVM, and VirtualBox. FVD is a holistic solution for both Cloud and non-Cloud environments. Its feature set includes flexible configurability, storage thin provisioning without a Host File System, compact image, internal snapshot, encryption, copy-on-write, copy-on-read, and adaptive prefetching. The last two features enable instant VM creation and instant VM migration, even if the VM image is stored on direct-attached storage. As its name indicates, FVD is fast. Experiments show that the throughput of FVD is 249% higher than that of QCOW2 when using the Post-Mark benchmark to create Files.

Pradeep K. Khosla - One of the best experts on this subject based on the ideXlab platform.

  • CHIMERA II : a real-time UNIX-compatible multiprocessor operating System for sensor-based control applications
    2018
    Co-Authors: David B. Stewart, Donald Schmitz, Pradeep K. Khosla
    Abstract:

    Abstract: "This paper describes the CHIMERA II multiprocessing operating System, which has been developed to provide the flexibility, performance, and UNIX-compatible interface needed for fast development and implementation of parallel real-time control code. The operating System is intended for sensor-based control applications such as robotics, process control, and manufacturing. The features of CHIMERA II include support for multiple general purpose CPUs; support for multiple special purpose processors and I/O devices; a UNIX-like environment, which supports most standard C System and library calls; standardized interrupt and exception handlers; and a user interface which serves as a terminal interface to the executing code. CHIMERA II also offers an attractive set of interprocessor communication features.The System-level express mail facility provides transparent access to a Host File System and remote devices, and provides the basis for implementing user-level interprocessor communication. Application programmers have the choice of using shared memory, message passing, remote semaphores, or other special synchronization primitives for communicating between multiple processors. As an example of an actual implementation, we are currently using CHIMERA II to control a multi-sensor based robot System. The System runs on a Sun workstation Host, with one or more Ironics M68020 processing boards, connected over a VME backplane. The System contains various special purpose processors, including a Mercury 3200 Floating Point Unit and an Androx Image Processor. The System also supports a variety of sensors and devices for real-time Systems, which currently include a camera, force and tactile sensors, and a joystick.

  • CHIMERA II: a real-time multiprocessing environment for sensor-based robot control
    Proceedings. IEEE International Symposium on Intelligent Control 1989, 1
    Co-Authors: David B. Stewart, D.e. Schmitz, Pradeep K. Khosla
    Abstract:

    The CHIMERA II multiprocessing environment has been developed for use in a wide variety of sensor-based robot Systems. It provides the flexibility, performance, and Unix-compatible interface needed for fast development of a real-time control code. The features of CHIMERA II include support for multiple general purpose CPUs; support for multiple special purpose CPUs and I/O devices; a real time multitasking kernel; user definable and dynamically selectable real-time schedulers; transparent access to a Host File System; generalized and efficient interprocess and interboard communication; remote process synchronization; standardized interrupt and exception handlers; Unix-like environment, which supports most standard C System and library calls; support for hierarchical and horizontal control architectures, such as NASREM; and a user interface which serves to download, monitor, and debug code on any processor board and serves as a terminal interface to the executing code. >

Anil Saini - One of the best experts on this subject based on the ideXlab platform.

  • sandfox secure sandboxed and isolated environment for firefox browser
    Security of Information and Networks, 2015
    Co-Authors: Anil Saini, Manoj Singh Gaur, Vijay Laxmi, Priyadarsi Nanda
    Abstract:

    Browser functionalities can be widely extended by browser extensions. One of the key features that makes browser extensions so powerful is that they run with "high" privileges. As a consequence, a vulnerable or malicious extension might expose browser, and operating System (OS) resources to possible attacks such as privilege escalation, information stealing, and session hijacking. The resources are referred as browser as well as OS components accessed through browser extension such as accessing information on the web application, executing arbitrary processes, and even access Files from a Host File System. This paper presents sandFOX (secure sandbox and iso- lated environment), a client-side browser policies for constructing sandbox environment. sandFOX allows the browser extension to express fine-grained OS specific security policies that are enforced at runtime. In particular, our proposed policies provide the protection to OS resources (e.g., Host File System, network and processes) from the browser attacks. We use Security-Enhanced Linux (SELinux) to tune OS and build a sandbox that helps in reducing potential damage from attacks on the OS resources. To show the practicality of sandFOX in a range of settings, we compute the effectiveness of sandFOX for various browser attacks on OS resources. We also show that sandFOX enabled browser experiences low overhead on loading pages and utilizes negligible memory when running with sandbox environment.

  • SIN - sandFOX: secure sandboxed and isolated environment for firefox browser
    Proceedings of the 8th International Conference on Security of Information and Networks - SIN '15, 2015
    Co-Authors: Anil Saini, Manoj Singh Gaur, Vijay Laxmi, Priyadarsi Nanda
    Abstract:

    Browser functionalities can be widely extended by browser extensions. One of the key features that makes browser extensions so powerful is that they run with "high" privileges. As a consequence, a vulnerable or malicious extension might expose browser, and operating System (OS) resources to possible attacks such as privilege escalation, information stealing, and session hijacking. The resources are referred as browser as well as OS components accessed through browser extension such as accessing information on the web application, executing arbitrary processes, and even access Files from a Host File System. This paper presents sandFOX (secure sandbox and iso- lated environment), a client-side browser policies for constructing sandbox environment. sandFOX allows the browser extension to express fine-grained OS specific security policies that are enforced at runtime. In particular, our proposed policies provide the protection to OS resources (e.g., Host File System, network and processes) from the browser attacks. We use Security-Enhanced Linux (SELinux) to tune OS and build a sandbox that helps in reducing potential damage from attacks on the OS resources. To show the practicality of sandFOX in a range of settings, we compute the effectiveness of sandFOX for various browser attacks on OS resources. We also show that sandFOX enabled browser experiences low overhead on loading pages and utilizes negligible memory when running with sandbox environment.

  • privacy leakage attacks in browsers by colluding extensions
    International Conference on Information Systems Security, 2014
    Co-Authors: Anil Saini, Manoj Singh Gaur, Vijay Laxmi, Tushar Singhal, Mauro Conti
    Abstract:

    Browser Extensions (BE) enhance the core functionality of the Browser and provide customization to it. Browser extensions enjoy high privileges, sometimes with the same privileges as Browser itself. As a consequence, a vulnerable or malicious extension might expose Browser and System resources to attacks. This may put Browser resources at risk of unwanted operations, privilege escalation etc. BE can snoop on web applications, launch arbitrary processes, and even access Files from Host File System. In addition to that, an extension can even collude with other installed extensions to share objects and change preferences. Although well-intentioned, extension developers are often not security experts. Hence, they might end up writing vulnerable code. In this paper we present a new attacks via Browser extensions. In particular, the attack allows two malicious extensions to communicate and collaborate with each other in such a way to achieve a malicious goal. We identify the vulnerable points in extension development framework as: (a) object reference sharing, and (b) preference overriding. We illustrate the effectiveness of the proposed attack using various attack scenarios. Furthermore, we provide a proof-of-concept illustration for web domains including Banking & shopping. We believe that the scenarios we use in use-case demonstration underlines the severity of the presented attack. Finally, we also contribute an initial framework to address the presented attack.

  • ICISS - Privacy Leakage Attacks in Browsers by Colluding Extensions
    Information Systems Security, 2014
    Co-Authors: Anil Saini, Manoj Singh Gaur, Vijay Laxmi, Tushar Singhal, Mauro Conti
    Abstract:

    Browser Extensions (BE) enhance the core functionality of the Browser and provide customization to it. Browser extensions enjoy high privileges, sometimes with the same privileges as Browser itself. As a consequence, a vulnerable or malicious extension might expose Browser and System resources to attacks. This may put Browser resources at risk of unwanted operations, privilege escalation etc. BE can snoop on web applications, launch arbitrary processes, and even access Files from Host File System. In addition to that, an extension can even collude with other installed extensions to share objects and change preferences. Although well-intentioned, extension developers are often not security experts. Hence, they might end up writing vulnerable code. In this paper we present a new attacks via Browser extensions. In particular, the attack allows two malicious extensions to communicate and collaborate with each other in such a way to achieve a malicious goal. We identify the vulnerable points in extension development framework as: (a) object reference sharing, and (b) preference overriding. We illustrate the effectiveness of the proposed attack using various attack scenarios. Furthermore, we provide a proof-of-concept illustration for web domains including Banking & shopping. We believe that the scenarios we use in use-case demonstration underlines the severity of the presented attack. Finally, we also contribute an initial framework to address the presented attack.

David B. Stewart - One of the best experts on this subject based on the ideXlab platform.

  • CHIMERA II : a real-time UNIX-compatible multiprocessor operating System for sensor-based control applications
    2018
    Co-Authors: David B. Stewart, Donald Schmitz, Pradeep K. Khosla
    Abstract:

    Abstract: "This paper describes the CHIMERA II multiprocessing operating System, which has been developed to provide the flexibility, performance, and UNIX-compatible interface needed for fast development and implementation of parallel real-time control code. The operating System is intended for sensor-based control applications such as robotics, process control, and manufacturing. The features of CHIMERA II include support for multiple general purpose CPUs; support for multiple special purpose processors and I/O devices; a UNIX-like environment, which supports most standard C System and library calls; standardized interrupt and exception handlers; and a user interface which serves as a terminal interface to the executing code. CHIMERA II also offers an attractive set of interprocessor communication features.The System-level express mail facility provides transparent access to a Host File System and remote devices, and provides the basis for implementing user-level interprocessor communication. Application programmers have the choice of using shared memory, message passing, remote semaphores, or other special synchronization primitives for communicating between multiple processors. As an example of an actual implementation, we are currently using CHIMERA II to control a multi-sensor based robot System. The System runs on a Sun workstation Host, with one or more Ironics M68020 processing boards, connected over a VME backplane. The System contains various special purpose processors, including a Mercury 3200 Floating Point Unit and an Androx Image Processor. The System also supports a variety of sensors and devices for real-time Systems, which currently include a camera, force and tactile sensors, and a joystick.

  • CHIMERA II: a real-time multiprocessing environment for sensor-based robot control
    Proceedings. IEEE International Symposium on Intelligent Control 1989, 1
    Co-Authors: David B. Stewart, D.e. Schmitz, Pradeep K. Khosla
    Abstract:

    The CHIMERA II multiprocessing environment has been developed for use in a wide variety of sensor-based robot Systems. It provides the flexibility, performance, and Unix-compatible interface needed for fast development of a real-time control code. The features of CHIMERA II include support for multiple general purpose CPUs; support for multiple special purpose CPUs and I/O devices; a real time multitasking kernel; user definable and dynamically selectable real-time schedulers; transparent access to a Host File System; generalized and efficient interprocess and interboard communication; remote process synchronization; standardized interrupt and exception handlers; Unix-like environment, which supports most standard C System and library calls; support for hierarchical and horizontal control architectures, such as NASREM; and a user interface which serves to download, monitor, and debug code on any processor board and serves as a terminal interface to the executing code. >