the following topics are dealt with: objectoriented programming; component based software development; realtimedistributedcomputing; realtime Java; software design; wireless and mobile networks; middleware; compo...
the following topics are dealt with: objectoriented programming; component based software development; realtimedistributedcomputing; realtime Java; software design; wireless and mobile networks; middleware; component execution support; sensor networks; scheduling and resource management; model-driven development; embedded systems; handling time faults; execution time analysis and program verification; and UML and modeling
In a real-timedistributedcomputing environment, security is critical to protect the system from unauthorized access especially since such systems are being used in time critical applications. Access Control mechanis...
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ISBN:
(纸本)076952561X
In a real-timedistributedcomputing environment, security is critical to protect the system from unauthorized access especially since such systems are being used in time critical applications. Access Control mechanisms have been introduced during the last several decades and have offered a basic and powerful means for enforcing security. In this paper, we examine the concepts of the TMO (time Triggered Message Triggered object) scheme that provides guaranteed real-time services in a distributedobjectcomputing environment. We also examine access control mechanisms;such as the traditional model, the RBAC (Role-based Access Control) model and the UCON (Usage Control) model. the main contribution of this paper is applying the traditional, RBAC and UCON models to the TMO scheme in order to provide a secure real-timedistributed environment.
For real-time systems we need time-predictable processors. this paper presents a method cache as a time-predictable solution for instruction caching. the method cache caches whole methods (or functions) and simplifies...
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ISBN:
(纸本)9781479944309
For real-time systems we need time-predictable processors. this paper presents a method cache as a time-predictable solution for instruction caching. the method cache caches whole methods (or functions) and simplifies worst-case execution time analysis. We have integrated the method cache in the time-predictable processor Patmos. We evaluate the method cache with a large set of embedded benchmarks. Most benchmarks show a good hit rate for a method cache size in the range between 4 and 16 KB.
Models for real-timecomputing are available with different timing requirements. Withthe ongoing trend towards integration of services of different degrees of timing strictness on one single platform, there is a need...
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ISBN:
(纸本)9781479944309
Models for real-timecomputing are available with different timing requirements. Withthe ongoing trend towards integration of services of different degrees of timing strictness on one single platform, there is a need to specify computing models for such scenarios. In this paper we study the requirements to specify mixed criticality real-time systems (MCRTS). Mixed criticality systems have been studied intensively over the last years. Existing formulations of the scheduling problem for mixed criticality systems do not consider the different timing strictness requirements of the tasks. In this paper we argue that mixed criticality properties as well as real-time properties have to be considered together in order to provide the maximal utility of a system. Based on that argument we present a list of ingredients required for the specification of MCRTS. We outline conceptually, how a system can take advantage of having MCRTS specifications available. We present some examples to show the usefulness of specifying MCRTS properties for real-life systems.
Standard real-time models do not consider the fact that a chosen technical deadline is different from the critical latency where the service utility becomes zero. this is in mismatch with engineering practice. In this...
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ISBN:
(纸本)9781479944309
Standard real-time models do not consider the fact that a chosen technical deadline is different from the critical latency where the service utility becomes zero. this is in mismatch with engineering practice. In this paper we propose a tolerance-based refinement of the real-time model. By doing so we make the process of deriving the estimation of the critical latency explicit. the difference between the technical deadline and the critical latency is a measure for the safety margin of the system. this safety margin is important for both, soft real-time and hard real-time systems, though with different quantities and qualities. Furthermore, we explain why the critical latency can hardly be quantified by a concrete value. However, we demonstrate how to derive reasonable estimates for it. We use a concrete application to show how the distinctive knowledge of the critical latency and the technical deadline are useful for real-time scheduling.
Active diagnosis aims at significantly improving system reliability by computing diagnostic information at run-time for fault isolation and online error recovery. the presented work extends semantic techniques, usuall...
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ISBN:
(纸本)9781479944309
Active diagnosis aims at significantly improving system reliability by computing diagnostic information at run-time for fault isolation and online error recovery. the presented work extends semantic techniques, usually used in large-scale IT systems, for active diagnosis in open embedded realtime systems. Open embedded systems (e.g., ambient assisted living for elderly care, critical infrastructures, health management and medical systems) exhibit real-time and reliability requirements, while the constituent components are unknown at design time. time-triggered diagnostic inference supports the incremental generation of symptoms, which result from the temporal and spatial decomposition of the diagnostic analysis process. the methods and algorithms are prototypically implemented, as well as experimentally evaluated. the paper demonstrates that dynamic semantic web services in combination withtime-triggered scheduling techniques are suitable to enable active diagnosis in open embedded systems with reliability and real-time requirements.
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