232 research outputs found

    Fault management of web services

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    The use of service-oriented (SO) distributed systems is increasing. Within service orientation web services (WS) are the de facto standard for implementing service-oriented systems. The consumers of WS want to get uninterrupted and reliable service from the service providers. But WS providers cannot always provide services in the expected level due to faults and failures in the system. As a result the fault management of these systems is becoming crucial. This work presents a distributed event-driven architecture for fault management of Web Services. According to the architecture the managed WS report different events to the event databases. From event databases these events are sent to the event processors. The event processors are distributed over the network. They process the events, detect fault scenarios in the event stream and manage faults in the WS

    A prototype and demonstrator of Akogrimo’s architecture: An approach of merging grids, SOA, and the mobile Internet

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    The trend of merging telecommunication infrastructures with traditional Information Technology (IT) infrastructures is ongoing and important for commercial service providers. The driver behind this development is, on one hand, the strong need for enhanced services and on the other hand, the need of telecommunication operators aiming at value-added service provisioning to a wide variety of customers. In the telecommunications sector, the IP Multimedia Subsystem (IMS) is a promising service platform, which may become a ''standard'' for supporting added-value services on top of the next generation network infrastructure. However, since its range of applicability is bound to SIP- enabled services, IMS extensions are being proposed by ''SIPifying'' applications. In parallel to these developments within the traditional IT sector, the notion of Virtual Organizations (VO) enabling collaborative businesses across organizational boundaries is addressed in the framework of Web Services (WS) standards implementing a Service-oriented Architecture (SOA). Here, concepts for controlled resource and service sharing based on WS and Semantic Technologies have been consolidated. Since the telecommunications sector has become, in the meantime ''mobile'', all concepts brought into this infrastructure must cope with the dynamics mobility brings in. Therefore, within the Akogrimo project the VO concept has been extended towards a Mobile Dynamic Virtual Organization (MDVO) concept, additionally considering key requirements of mobile users and resources. Especial attention is given to ensure the duality of the merge of both, SOA and IMS approaches to holistically support SOA-enabled mobile added-value services and their users. This work describes major results of the Akogrimo project, paying special attention to the overall Akogrimo architecture, the prototype implemented, and the key scenario in which the instantiated Akogrimo architecture shows a very clear picture of applicability, use, and an additional functional evaluation

    A Generic Network and System Management Framework

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    Networks and distributed systems have formed the basis of an ongoing communications revolution that has led to the genesis of a wide variety of services. The constantly increasing size and complexity of these systems does not come without problems. In some organisations, the deployment of Information Technology has reached a state where the benefits from downsizing and rightsizing by adding new services are undermined by the effort required to keep the system running. Management of networks and distributed systems in general has a straightforward goal: to provide a productive environment in which work can be performed effectively. The work required for management should be a small fraction of the total effort. Most IT systems are still managed in an ad hoc style without any carefully elaborated plan. In such an environment the success of management decisions depends totally on the qualification and knowledge of the administrator. The thesis provides an analysis of the state of the art in the area of Network and System Management and identifies the key requirements that must be addressed for the provisioning of Integrated Management Services. These include the integration of the different management related aspects (i.e. integration of heterogeneous Network, System and Service Management). The thesis then proposes a new framework, INSMware, for the provision of Management Services. It provides a fundamental basis for the realisation of a new approach to Network and System Management. It is argued that Management Systems can be derived from a set of pre-fabricated and reusable Building Blocks that break up the required functionality into a number of separate entities rather than being developed from scratch. It proposes a high-level logical model in order to accommodate the range of requirements and environments applicable to Integrated Network and System Management that can be used as a reference model. A development methodology is introduced that reflects principles of the proposed approach, and provides guidelines to structure the analysis, design and implementation phases of a management system. The INSMware approach can further be combined with the componentware paradigm for the implementation of the management system. Based on these principles, a prototype for the management of SNMP systems has been implemented using industry standard middleware technologies. It is argued that development of a management system based on Componentware principles can offer a number of benefits. INSMware Components may be re-used and system solutions will become more modular and thereby easier to construct and maintain

    Securing critical utility systems & network infrastructures

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    Tese de mestrado, Segurança Informática, Universidade de Lisboa, Faculdade de Ciências, 2009As infra-estruturas críticas de TI para serviços públicos são apoiadas por inúmeros sistemas complexos. Estes sistemas permitem a gestão e recolha de informação em tempo-real, constituindo a base para a gestão eficiente das operações. A utilização, cada vez mais frequente, de software e hardware (Commercial Off-The-Shelf, COTS) em sistemas SCADA permitiu grandes beneficios financeiros na aquisição e desenvolvimento de soluções técnicas que suportam os serviços públicos. O uso de hardware e software COTS em sistemas SCADA transferiu para as infra-estruturas críticas os problemas de segurança de uma infraestrutura de TI empresarial. Neste contexto, um desafio para as equipas de gestão operacional dos sistemas de TI é a gestão eficaz dos sistemas e redes que compõem as infra-estruturas críticas dos serviços públicos. Apesar de estas organizações adoptarem, cada vez mais, normas e melhores práticas que visam melhorar a gestão, operações e processos de configuração. Este projecto de investigação propõe-se a desenvolver um estudo comparativo de plataformas de gestão integrada no contexto dos sistemas SCADA que suportam serviços públicos. Adicionalmente, este projecto de investigação irá desenvolver estudos acerca de perfis operacionais dos Sistemas Operativos que suportam a infra-estrutura IT dos serviços públicos críticos. Este projecto de investigação irá descrever como as decisões estratégicas de gestão têm impacto nas operações de gestão de uma infra-estrutura TI.Modern critical utility IT infrastructures are supported by numerous complex systems. These systems allow real-time management and information collection, which is the basis of efficient service management operations. The usage of commercial off-the-shelf (COTS) hardware and software in SCADA systems allowed for major financial advantages in purchasing and developing technical solutions. On the other hand, this COTS hardware and software generalized usage in SCADA systems, exposed critical infrastructures to the security problems of a corporate IT infrastructure. A significant challenge for IT teams is managing critical utility IT infrastructures even upon adopting security best practices that help management, operations and configuration of the systems and network components that comprise those infrastructures. This research project proposes to survey integrated management software that can address the specific security constraints of a SCADA infrastructure supported by COTS software. Additionally, this research project proposes to investigate techniques that will allow the creation of operational profiles of Operating Systems supporting critical utility IT infrastructures. This research project will describe how the strategic management decisions impact tactical operations management of an IT environment. We will investigate desirable technical management elements in support of the operational management

    Threats and Defenses in SDN Control Plane

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    abstract: Network Management is a critical process for an enterprise to configure and monitor the network devices using cost effective methods. It is imperative for it to be robust and free from adversarial or accidental security flaws. With the advent of cloud computing and increasing demands for centralized network control, conventional management protocols like Simple Network Management Protocol (SNMP) appear inadequate and newer techniques like Network Management Datastore Architecture (NMDA) design and Network Configuration (NETCONF) have been invented. However, unlike SNMP which underwent improvements concentrating on security, the new data management and storage techniques have not been scrutinized for the inherent security flaws. In this thesis, I identify several vulnerabilities in the widely used critical infrastructures which leverage the NMDA design. Software Defined Networking (SDN), a proponent of NMDA, heavily relies on its datastores to program and manage the network. I base my research on the security challenges put forth by the existing datastore’s design as implemented by the SDN controllers. The vulnerabilities identified in this work have a direct impact on the controllers like OpenDayLight, Open Network Operating System and their proprietary implementations (by CISCO, Ericsson, RedHat, Brocade, Juniper, etc). Using the threat detection methodology, I demonstrate how the NMDA-based implementations are vulnerable to attacks which compromise availability, integrity, and confidentiality of the network. I finally propose defense measures to address the security threats in the existing design and discuss the challenges faced while employing these countermeasures.Dissertation/ThesisMasters Thesis Computer Science 201

    Accurate and Resource-Efficient Monitoring for Future Networks

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    Monitoring functionality is a key component of any network management system. It is essential for profiling network resource usage, detecting attacks, and capturing the performance of a multitude of services using the network. Traditional monitoring solutions operate on long timescales producing periodic reports, which are mostly used for manual and infrequent network management tasks. However, these practices have been recently questioned by the advent of Software Defined Networking (SDN). By empowering management applications with the right tools to perform automatic, frequent, and fine-grained network reconfigurations, SDN has made these applications more dependent than before on the accuracy and timeliness of monitoring reports. As a result, monitoring systems are required to collect considerable amounts of heterogeneous measurement data, process them in real-time, and expose the resulting knowledge in short timescales to network decision-making processes. Satisfying these requirements is extremely challenging given today’s larger network scales, massive and dynamic traffic volumes, and the stringent constraints on time availability and hardware resources. This PhD thesis tackles this important challenge by investigating how an accurate and resource-efficient monitoring function can be realised in the context of future, software-defined networks. Novel monitoring methodologies, designs, and frameworks are provided in this thesis, which scale with increasing network sizes and automatically adjust to changes in the operating conditions. These achieve the goal of efficient measurement collection and reporting, lightweight measurement- data processing, and timely monitoring knowledge delivery
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