Developing fault tolerant ambient systems requires many challenging factors to be considered due to the nature of such systems, which tend to contain a lot of mobile elements that change their behaviour depending on t...
详细信息
ISBN:
(纸本)9780769527659
Developing fault tolerant ambient systems requires many challenging factors to be considered due to the nature of such systems, which tend to contain a lot of mobile elements that change their behaviour depending on the surrounding environment, as well as the possibility of their disconnection and re-connection. It is therefore necessary to construct the critical parts of fault tolerant ambient systems in a rigorous manner this can be achieved by deploying formal approach at the design stage, coupled with sound framework and support at the implementation stage. In this paper we briefly describe a middleware that we developed to provide system structuring through the concepts of roles, agents, locations and scopes, making it easier for the developers to achieve fault tolerance. We then outline our experience in developing an ambient lecture system using the combination of formal approach and our middleware.
Recently, new trends in application development for distributed platforms, such as the composable services model, attempt to provide more flexibility in system design, deployment and execution. Such trends, and partic...
详细信息
ISBN:
(纸本)9780769527659
Recently, new trends in application development for distributed platforms, such as the composable services model, attempt to provide more flexibility in system design, deployment and execution. Such trends, and particularly the referred composable services model, can also be beneficial in real-timedistributed embedded systems, also providing a means to support more adaptive behaviors, reacting to the execution environment or coping with system. reconfiguration. this paper explores a relatively new direction, which is the extension of the service-based model to dynamic, i.e. at run-time, composition in real-timedistributed environments, in order to support the level of flexibility and adaptibility referred above. the paper proposes an architecture to support such dynamic service composition that is based on the Flexible time Triggered communication paradigm (FTT). To achieve the desired goal, we also redefine the concepts of service and service-based application in the concept of the FTT paradigm. Finally, we show experimental results obtained with a prototype implementation of the proposed architecture that confirm its feasibility and good temporal behavior
Standards-based quality of service (QoS)-enabled Component middletvare is increasingly being used as a platform,for developing distributedreal-time embedded (DRE) systems that execute in open environments where opera...
详细信息
ISBN:
(纸本)9780769527659
Standards-based quality of service (QoS)-enabled Component middletvare is increasingly being used as a platform,for developing distributedreal-time embedded (DRE) systems that execute in open environments where operational conditions, input workload, and resource availability cannot be characterized accurately a priori. Although QoS-enabled component middleware offers many desirable features, until recently it lacked the ability to efficiently allocate resources and configure platform-specific QoS settings based on utilization of system resources and application QoS. Moreover, it has also lacked the ability to monitor and enforce application QoS requirements. this paper presents two contributions to research on adaptive resource management for component-based DRE systems. First, we describe the structure and functionality of the Resource Allocation and Control Engine (RACE), which is an open-source adaptive resource management framework built atop standards-based QoS-enabled component iniddleware. Second, we demonstrate the effectiveness of RACE in the context of a representative DREsystem: NASA's Magnetospheric Multi-scale Mission system.
During the last years, component based software development has become a well accepted software engineering paradigm within the automotive industry. this fact is not only reflected by upcoming development tools but al...
详细信息
ISBN:
(纸本)9780769527659
During the last years, component based software development has become a well accepted software engineering paradigm within the automotive industry. this fact is not only reflected by upcoming development tools but also by newly arising automotive software standards. In component based software engineering, applications are built by assembling small reusable building blocks, the components. Typically more than one component implementation meets the application developer's requirements, so proper selection of the assembled components becomes a key element of the whole procurement and engineering process. this paper's contribution is twofold: First, a basic set of performance and dependability metrics and measures for automotive components is identified. Second, a unified benchmarking process is proposed, that allows an unambiguous comparison of distinct component implementations of a given component class.
this paper describes the parallelization (gridification) of the phylogenetic pack-age PHYLIP on a Large Scale distributed System termed XtremWeb-CH. PHYLIP is a pack-age of programs for inferring phylogenies (evolutio...
详细信息
ISBN:
(纸本)9780769528335
this paper describes the parallelization (gridification) of the phylogenetic pack-age PHYLIP on a Large Scale distributed System termed XtremWeb-CH. PHYLIP is a pack-age of programs for inferring phylogenies (evolutionary trees). It is the most widely-distributed phylogeny-package. PHYLIP has been used to build the largest number of published trees. It's known that some modules of PHYLIP are CPU time consuming;their sequential version can not be applied to a large number of sequences. XtremWeb-CH (XWCH) is a software system that makes it easier for scientists and industrials to deploy and execute their parallel and distributed applications on a public-resource computing infrastructure. Universities, research centres and private companies can create their own XWCH platform while anonymous PC owners can participate to these platforms. they can specify how and when their resources could be used. the objective of XWCH is to develop a real High Performance Peer-To-Peer platform with a distributed scheduling and communication system. the main idea is to build a completely symmetric model where nodes can be providers and consumers at the same time. In this paper we describe the porting, deployment, and execution of some PHYLIP modules on the XWCH platform. the parallelized version of PHYLIP is used to generate evolutionary tree related to HIV viruses.
Grid technology allows resource sharing among several entities, but selecting the best resource to run a specific job remains one of its main problems. the challenges for the best resource selection involve analysis o...
详细信息
ISBN:
(纸本)9780769528335
Grid technology allows resource sharing among several entities, but selecting the best resource to run a specific job remains one of its main problems. the challenges for the best resource selection involve analysis of several factors such as prediction time to run a job, access restriction to resources, and cost to use resources. this paper presents a resource selection model using decision theory for combining these influential factors in the resource selection process. the model is based on a multi-attribute utility function that maximizes the user preference. this model forms part of a multi-agent system deploying distributed and parallel processing for job execution prediction, access policy verification, and resource selection models. All models of this paper were verified through experiments using real machines. they have presented appropriate functional behaviors and positive performance results.
In object-orientedreal-timecomputing scenarios, particularly where Corba is used in embedded systems with resource constraints, developers and system architects often utilize Corba object references as authorization...
详细信息
In object-orientedreal-timecomputing scenarios, particularly where Corba is used in embedded systems with resource constraints, developers and system architects often utilize Corba object references as authorization tokens. this paper investigates the security of this method in principle, and it presents the results of the analysis of the work and computing effort necessary for a potential attacker to fabricate Corba object references to existing objects for the purpose of illegitimately gaining access to these objects at the instance of seven widely used Corba products
Requirements of high integrity systems now encompass distribution mechanisms along with strong functional and non-functional features (run-time support for hardware, dependability, safety, analyzability). In this pape...
详细信息
Requirements of high integrity systems now encompass distribution mechanisms along with strong functional and non-functional features (run-time support for hardware, dependability, safety, analyzability). In this paper, we show how model processing help addressing such needs. We present a generic distribution model suitable for high integrity systems, and demonstrate how a high-level modeling deployment view allows one to greatly reduce the model complexity. Finally, we conclude by assessing a case study
暂无评论