2012 7th IEEE International Symposium on Industrial Embedded Systems (SIES)

Conference Information
Name: 2012 7th IEEE International Symposium on Industrial Embedded Systems (SIES)
Location: Karlsruhe, Germany
Date: 2012-6-20 - 2012-6-22

Latest articles from this conference

Rene Graf
Summary form only given, as follows. Automation is just one application field of embedded systems, but surely one of the most heterogeneous ones. Automation systems can be found in very different places like traffic control, home and building automation, but also in industrial scenarios like production of cars or petrochemical plants. The first part of the keynote will take the audience on a journey through this variety. Both real time requirements and applications of these domains will be presented. Furthermore, common trends like multicore processors enter the field of automation systems as well, but the consequences of using multicore processors in hard real time devices are not understood completely so far. The second part of the keynote will present a real life example of loosing performance by using two cores instead of one. The most important conclusion is that hardware and software have implicit dependencies, which have to be considered in the very early system design phase.
Summary form only given, as follows. As technology scales to 22nm and beyond, reliability becomes a serious concern of densely integrated on-chip systems. Aging effects like electro-migration, NBTI (Negative Bias Temperature Instability), TDDB (Time Dependent Dielectric Breakdown) and other effects alter the electric characteristics of circuits and lead finally to transient and/or permanent faults. High temperature often accelerates these effects and can be seen as a trigger for many known aging effects. But not only aging effects, also various kinds of particle strikes jeopardize reliability as CMOS technology scales to deep nano-scale. In fact, particle strikes may lead to transient bit-flips. All these effects are already observed today and will worsen with each upcoming technology node. So far, mostly physical-level and device-level techniques have been applied to control these negative effects that represent a major hurdle for further technology scaling. However, also architectural-level techniques have been successfully applied. Going even a step further up, we propose to include the whole software stack all the way up to the applications software to control these negative effects. We will show means in form of a few basic software transformations that can contribute to increase reliability in deep nano-scale systems. We emphasize the potential of cross-layer approaches and contribute to the paradigm "Reliable Software for Unreliable Hardware: Embedded Code Generation aiming at Reliability."
Manuel Cheminod, , Adriano Valenzano
Awareness that networked embedded systems are vulnerable to cyber-threats has been constantly raising since some years ago. In the industrial arena recent severe attacks, such as the popular case of the Stuxnet worm, have completely debunked the myth of security of embedded devices based on their isolation. Indeed, the ever increasing dependence of many industrial systems on digital communication networks is causing the cyber-security requirements to become a priority in their planning, design, deployment and management. This paper deals with our experience in checking the conformance of a distributed industrial automation system, which includes several types of embedded devices, with respect to a set of security policies defined at the global system level. In particular, the focus of the paper is on the use of modeling techniques and semi-automated s/w tools to verify the configuration of devices and services with attention to the correct use of their security capabilities to support the desired set of policies.
Emanuel Heidinger, Fabien Geyer, Stefan Schneele, Michael Paulitsch
Audio-Video-Bridging (AVB) is a promising new commercially available Ethernet-based standard providing mechanism for audio and video transmission over Ethernet supporting demanding audio and video transmission delay requirements. This paper addresses the applicability of using AVB in a fully-switched Ethernet network that covers safety-related functions in the aeronautics. Avionic systems leveraging such digital networks have stringent requirements in terms of audio quality, latency, and jitter; e.g., latency can be at most a few milliseconds. The result of this work is a performance study of audio transmission approaches in aeronautics where we address AVB without synchronization and AVB synchronization with 802.1AS. We pay special attention to the failure mode of losing synchronization during operation. Two real-world scenarios are addressed in the experimental results - a demonstration of a switched Ethernet aircraft cabin and a demonstration for a highly safety-related audio system. For these two scenarios hard performance bounds are required in terms of synchronous playback that cannot easily be fulfilled, especially when time synchronization is lost.
Stefan Stattelmann, Sebastian Ottlik, Alexander Viehl, Oliver Bringmann, Wolfgang Rosenstiel
Simulation-based approaches to evaluate the functional and non-functional properties of embedded software are in widespread industrial use for design space exploration and virtual prototyping. As simulation performance is usually the main concern for these tools, they often lack an accurate timing model of the underlying processor. On the other hand, tools aimed at the worst-case execution time (WCET) analysis of embedded software contain accurate models for the timing behavior of embedded processors. Yet, these accurate processor models are only used to determine the worst-case path through the analyzed program. This paper proposes the combination of existing tools from both domains. The combination of an a priori analysis of machine code with a dynamic selection of basic block timing estimates during the execution of the program in a high-speed instruction set simulator (ISS) reduces the simulation overhead for cycle-accurate timing estimation. By keeping track of the execution history during execution of the analyzed software, the full accuracy of the offline performance model can be used without introducing pessimism to the simulation-based performance estimates. As most of the timing estimation is done before the simulation, only a slight decrease in simulation performance of the high-speed ISS can be expected.
Sjoerd Cranen, Reinder J. Bril
Hierarchical scheduling frameworks (HSFs) provide means for composing complex real-time systems from well-defined independently developed and analyzed subsystems. To support shared logical resources requiring mutual exclusive access in two-level HSFs, overrun without payback has been proposed as a mechanism to prevent budget depletion during resource access arbitrated by the stack resource policy (SRP). The same mechanism can be applied to support scheduling techniques, such as fixed-priority scheduling with deferred preemption (FPDS), that aim at a reduction of the architecture-related preemption costs and may improve the feasibility of a system. Whereas the blocking times and overrun budgets for shared logical resources will typically be much smaller than the normal budget, these values may significantly increase for scheduling techniques such as FPDS. In this paper, we therefor consider replenishment-bounded overrun, i.e. the overrun ends upon a replenishment, because the normal budget becomes available again, which allows for larger overrun budgets. We show that the global schedulability analysis for this special kind of overrun has a number of anomalies: (i) the usual theorem for critical instant does not hold, (ii) maximal blocking does not necessarily lead to a maximal response time, and (iii) it is not sufficient to analyse a fixed amount of time (say, a number of hyperperiods). We present analysis for two subsystems.
Claude-Pierre Jeannerod, Jingyan Jourdan-Lu, Christophe Monat
This paper presents some work in progress on the design and implementation of efficient floating-point software support for embedded integer processors. We provide quantitative evidence of the benefits of supporting various non-generic (that is, fused, specialized, or paired) operations in addition to the five basic arithmetic operations: for individual calls, speedups range from 1.12 to 4.86, while on DSP kernels and benchmarks, our approach allows us to be up to 1.59x faster.
Christian Prehofer, Marc Zeller
In this work, we consider reliable runtime adaptation in networked, embedded systems with tight real-time constraints by adapting the placement of software components on a multitude of hardware components. We show the need for a hierarchical transaction concept in this context. In particular, we consider multiple adaptation steps under hard system constraints and also introduce a model with undesired configurations, which cannot be maintained for an extended time period. Furthermore, we discuss implementation issues for such an adaptation process, including the actual task migration implementation, for real-time, embedded systems.
, Stefan M. Petters
A large part of power dissipation in a system is generated by I/O devices. Increasingly these devices provide power saving mechanisms, inter alia to enhance battery life. While I/O device scheduling has been studied in the past for real-time systems, the use of energy resources by these scheduling algorithms may be improved. These approaches are crafted considering a very large overhead of device transitions. Technology enhancements have allowed the hardware vendors to reduce the device transition overhead and energy consumption. We propose an intra-task device scheduling algorithm for real time systems that allows to shut-down devices while ensuring system schedulability. Our results show an energy gain of up to 90% when compared to the techniques proposed in the state-of-the-art.
, Jukka Maki-Turja, Mikael Sjodin
The existing response-time analysis for messages in Controller Area Network (CAN) with CAN controllers facilitating transmission abort requests in transmission buffers does not support mixed messages. The existing analysis assumes that a message is queued for transmission either periodically or sporadically. However, a message can also be queued both periodically and sporadically using a mixed transmission mode implemented by several high-level protocols for CAN used in the industry today. We extend the existing analysis for mixed messages in CAN which is generally applicable to any high-level protocol that uses periodic, sporadic and mixed transmission modes and supports transmission abort requests in CAN controllers.
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