In this paper, we show that the scheduling of tests on the test access mechanism (TAM) is equivalent to independent job scheduling on identical machines and we make use of all existing preemptive scheduling algorithm ...
详细信息
In this paper, we show that the scheduling of tests on the test access mechanism (TAM) is equivalent to independent job scheduling on identical machines and we make use of all existing preemptive scheduling algorithm to produce an optimal solution in linear time. We extend the algorithm to handle (1) test conflicts elite to interconnection tests and (2) cases when a test limits all optimal usage of the TAM by using reconfigurable core test wrappers. Our extensions preserve the production of all optimal solution in respect to test time and minimizes the number of wrapper configurations as well as the TAM usage at each core. which implicitly minimizes the TAM routing. Experiments with our implementation shows its efficiency in comparison with previous approaches.
The spreading of Ethernet TCP/IP protocol suite based communication in automation systems has raised new questions concerning data consistency and security. We introduce temporal-logic RBAC as a method to formalise th...
详细信息
The spreading of Ethernet TCP/IP protocol suite based communication in automation systems has raised new questions concerning data consistency and security. We introduce temporal-logic RBAC as a method to formalise the security relevant access constraints for an agent based control system. We also offer some examples of such formalised constraints generated from constraints that were originally written down in human language. The authors point out that temporal-logic RBAC might thus be helpful to cope with the new problems of information security in plant automation.
The problems related to supporting multicast connections with quality of service (QoS) requirements are studied. We investigate the problem of optimal resource allocation in the context of performance dependent costs....
详细信息
The problems related to supporting multicast connections with quality of service (QoS) requirements are studied. We investigate the problem of optimal resource allocation in the context of performance dependent costs. In this context each network element can offer several QoS guarantees, each associated with a different cost. This is a natural extension to the commonly used bi-criteria model, where each link is associated with a single delay and a single cost. This framework is simple yet strong enough to model many practical interesting networking problems. The fundamental multicast resource allocation problem under this framework is how to optimally allocate QoS requirements on the links of the multicast tree. One needs to partition the end-to-end QoS requirement along the various paths in a tree. The goal is to satisfy the end-to-end QoS requirement with minimum cost. Previous studies under this framework considered single-source multicast connections, where the end-to-end QoS requirement is specified from the source to all other multicast group members. In this paper we extend these results to the more general, and considerably harder case of multicast sessions, where the end-to-end requirement hold for every path between any two multicast group members. Our aim is to provide rigorous solutions, with proven performance guarantees, by way of algorithmic analysis. The problem under investigation is NP hard for general cost functions, thus we first present a pseudopolynomial exact solution. From this solution we derive two efficient /spl epsi/-approximate solutions. One achieves optimal cost, but may violate the end-to-end delay requirement by a factor of (1 + /spl epsi/), and the other strictly obeys the bounds and achieves a cost within a factor of (1+/spl epsi/) of the optimum. Furthermore, we present improved results for discrete cost functions, and give a simple linear-time exact polynomial solution for a specific, and practically interesting, family of convex
We consider the type inference problems in a compositional design environment where the components are automatically instantiated from pre-existing C++-based intellectual property (IP) libraries. We present a componen...
详细信息
ISBN:
(纸本)9780780376601
We consider the type inference problems in a compositional design environment where the components are automatically instantiated from pre-existing C++-based intellectual property (IP) libraries. We present a component integration language based on scripting for design specification. Our focus is the architectural aspects in the specification that use aggregation - as opposed to the more commonly used inheritance - for composition of components. Our approach simplifies architectural specification by employing a type inference and type management environment. We show that the type inference problem is NP-complete. We present a heuristic based on code generation and parameterization to solve the type inference for IP selection in our C++-based composition environment. We have implemented the composition and type management in the BALBOA framework. The results show the utility of our approach.
This paper argues for strong notions of Object Schizophrenia (OS) and Object Schizophrenia Problem (OSP) and makes subtle distinction between them. It presents how OSP can occur in modeling ispart- of and is-role-of r...
详细信息
embeddedsystems are typically designed for one or a few target applications, allowing for customization of the system architecture for the desired system goals such as performance, power and cost. The memory subsyste...
详细信息
This paper describes a concept based on application adaptivity and Differentiated Services (DiffServ) in order to provide the quality-of-service (QoS) required by real-time applications. Assuming the availability of d...
详细信息
ISBN:
(纸本)0780373715
This paper describes a concept based on application adaptivity and Differentiated Services (DiffServ) in order to provide the quality-of-service (QoS) required by real-time applications. Assuming the availability of different service classes, we propose that a real-time application always selects the lowest/cheapest service class that still can meet the application requirements. The selection depends on RTP-based QoS monitoring and on additional probing of the quality of the next lower service class. The service class selection algorithm has been implemented within an IP telephony application and evaluated in a test-bed consisting of Linux-PC based DiffServ routers. The evaluation proves the suitability of the approach but also shows several issues for further improvement.
This paper proposes a novel real-time adaptive admission control (AAC) scheme with a desired quality of service (QoS) guarantee and high network utilization in high-speed networks. The QoS is given in terms of service...
详细信息
This paper proposes a novel real-time adaptive admission control (AAC) scheme with a desired quality of service (QoS) guarantee and high network utilization in high-speed networks. The QoS is given in terms of service delay, which is defined as the time it takes for a source to get admitted into the network after it initiates its intended request, packet/cell losses, and transmission delay (time taken to complete transmission from its initiation). AAC uses the following information- the available capacity from a novel adaptive bandwidth estimation scheme, a congestion indicator derived from a congestion controller, Peak Cell Rate (PCR) estimate from new sources, along with the desired QoS metrics, and outputs an 'admit' or 'reject' decision signal to the new sources while guaranteeing QoS and network utilization. Simulation results are presented by streaming ON/OFF and video data into the network. Results show that the proposed AAC admits significantly more traffic compared to other available admission control schemes thereby guaranteeing high network utilization while maintaining the desired QoS.
This paper proposes a novel real-time adaptive admission control (AAC) scheme with a desired quality of service (QoS) guarantee and high network utilization in high speed networks. The QoS is given in terms of service...
详细信息
This paper proposes a novel real-time adaptive admission control (AAC) scheme with a desired quality of service (QoS) guarantee and high network utilization in high speed networks. The QoS is given in terms of service delay, which is defined as the time it takes for a source to get admitted into the network after it initiates its intended request, packet/cell losses, and transmission delay (time taken to complete transmission from its initiation). AAC uses the following information - the available capacity from a novel adaptive bandwidth estimation scheme, a congestion indicator derived from a congestion controller, peak cell rate estimate from new sources, along with the desired QoS metrics, and outputs an 'admit' or 'reject' decision signal to the new sources while guaranteeing QoS and network utilization. Simulation results are presented by streaming ON/OFF and video data into the network. Results show that the proposed AAC admits significantly more traffic compared to other available admission control schemes thereby guaranteeing high network utilization while maintaining the desired QoS.
暂无评论