Copilot: monitoring embedded systems

Runtime verification (RV) is a natural fit for ultra-critical systems that require correct software behavior. Due to the low reliability of commodity hardware and the adversity of operational environments, it is common in ultra-critical systems to replicate processing units (and their hosted software) and incorporate fault-tolerant algorithms to compare the outputs, even if the software is considered to be fault-free. In this paper, we investigate the use of software monitoring in distributed fault-tolerant systems and the implementation of fault-tolerance mechanisms using RV techniques. We describe the Copilot language and compiler that generates monitors for distributed real-time systems, and we discuss two case-studies in which Copilot-generated monitors were used to detect onboard software and hardware faults and monitor air-ground data link messaging protocols.     

并行分布式计算机样机的监测测试

介绍了一个基于联机实时监测的方案,它采用了作者研制的ＭＳ－１监测系统。该系统是一个具有同步实时时钟的分布式监测系统,采用事件驱动的软硬件混合监测方式,联机实时监测软件ＯＭ把监测系统的控制与监测数据的采集和观测分析结合起来,完成了联机监测与分析,用来及时提供系统的内部状态信息和动态行为。     

Risk Assessment of Computer Controlled Systems

Software is increasingly being used to control and monitor systems for which safety and reliability are critical. When comparing software designs for such systems, an evaluation of how each design can contribute to the risk of system failure is desirable. Unfortunately, the science of risk assessment of combined hardware and software systems is in its infancy. Risk assessment of combined hardware/software systems is often based on oversimplified assumptions about software behavior.     

Monitoring applications: An immune inspired algorithm for software-fault detection

Large-scale software systems are in general difficult to manage and monitor. In many cases, these systems display unexpected behavior, especially after being updated or when changes occur in their environment (operating system upgrades or hardware migrations, to name a few). Therefore, to handle a changing environment, it is desirable to base fault detection and performance monitoring on self-adaptive techniques.Several studies have been carried out in the past which, inspired on the immune system, aim at solving complex technological problems. Among them, anomaly detection, pattern recognition, system security and data mining are problems that have been addressed in this framework.There are similarities between the software fault detection problem and the identification of the pathogens that are found in natural immune systems. Being inspired by vaccination and negative and clonal selection observed in these systems, we developed an effective self-adaptive model to monitor software applications analyzing the metrics of system resources.     

A model and methodology for hardware-software codesign

A behavioral model of a class of mixed hardware-software systems is presented. A codesign methodology for such systems is defined. The methodology includes hardware-software partitioning, behavioral synthesis, software compilation, and demonstration on a testbed consisting of a commercial central processing unit (CPU), field-programmable gate arrays, and programmable interconnections. Design examples that illustrate how certain characteristics of system behavior and constraints suggest hardware or software implementation are presented     

A safe, accurate intravenous infusion control system

Medical facilities use conventional intravenous (IV) infusion systems in cases where the patient needs some kind of programmed medicine or nutrition. Gravity controls the simplest and cheapest system. In this kind of system, however, the flow rate varies with the bottle's fluid volume and the hose's pressure. Adjusting the drip feed keeps the rate constant. This article details our development of a control system for conventional gravity-controlled infusion systems that guarantees a safe and accurate infusion process. The control system measures the current flow rate through an optical sensor in the drop window and controls it by compressing or decompressing the hose with a motor. We wanted the system to control conventional IV infusion systems with hardware and software. This kind of implementation creates a low-cost control system that resists software faults. Providing this kind of safety becomes crucial if the microcomputer is also used for other purposes. To analyze the various implementation possibilities, we used the PISH (integrated design of software and hardware) codesign methodology developed by our research group. This fault-tolerant system implemented in hardware and software and partitioned with a codesign methodology revolutionizes traditional IV infusion control systems     

Bird classification based on their sound patterns

In this paper we focus on automatic bird classification based on their sound patterns. This is useful in the field of ornithology for studying bird species and their behavior based on their sound. The proposed methodology may be used to conduct survey of birds. The proposed methods may be used to automatically classify birds using different audio processing and machine learning techniques on the basis of their chirping patterns. An effort has been made in this work to map characteristics of birds such as size, habitat, species and types of call, on to their sounds. This study is also part of a broader project that includes development of software and hardware systems to monitor the bird species that appear in different geographical locations which helps ornithologists to monitor environmental conditions with respect to specific bird species.     

基于dsPIC30F6012的变压器监测系统终端设计

变压器监测系统是电力自动化系统的重要组成部分。本文以处理器dsPIC30F6012和电能芯片ATT7022A为基础,设计了基于GPRS的变压器监测系统数据采集终端,给出了系统各个部分的硬件电路设计,在此基础上对系统软件进行设计并给出软件流程图。设计的变压器监测终端硬件电路简单,易于实现,具有一定的参考实用价值。     

基于STC89C52计算机监控学习机的研制

计算机监控系统集成了计算机软件、硬件和信息通信系统,并广泛应用于众多领域。本文以STC89C52单片机为核心研制了一台计算机监控学习机,通过USB接口获取电源,利用RS-232接口与上位机通信,集成了模拟量输入、开关量输入与输出,设计了通信协议,妥善解决了内部通信问题,并通过了"通用多功能计算机监控系统测试软件"的测试。该计算机监控学习机可以用来实践计算机监控系统相关的软件开发技能和硬件设计技能,对培养应用型人才具有重要意义。     

基于消息中间件的车辆GPS监控系统框架的设计

GPS车辆监控系统是一种结合车载GPS终端和GIS等各种软、硬件技术的先进的车辆监控手段。本文讨论设计的基于消息中间件的监控系统框架,是一种以消息服务为核心的低耦合、高内聚的框架,其设计目标是能够支撑一个集中部署的大型系统,为分布于各地的数十万车辆提供稳定、高效的监控服务。经过实践的检验,该框架切实可行,可以胜任超大型车辆监控系统的设计与实现。     

Intel virtualization technology

A virtualized system includes a new layer of software, the virtual machine monitor. The VMM's principal role is to arbitrate accesses to the underlying physical host platform's resources so that multiple operating systems (which are guests of the VMM) can share them. The VMM presents to each guest OS a set of virtual platform interfaces that constitute a virtual machine (VM). Once confined to specialized, proprietary, high-end server and mainframe systems, virtualization is now becoming more broadly available and is supported in off-the-shelf systems based on Intel architecture (IA) hardware. This development is due in part to the steady performance improvements of IA-based systems, which mitigates traditional virtualization performance overheads. Intel virtualization technology provides hardware support for processor virtualization, enabling simplifications of virtual machine monitor software. Resulting VMMs can support a wider range of legacy and future operating systems while maintaining high performance.     

嵌入式虚拟化技术

计算机系统虚拟化技术是IT领域近几年的热点技术。虚拟化技术的下一步发展方向是嵌入式系统。嵌入式系统进行虚拟化是在嵌入式硬件平台和操作系统之间加入一层叫做虚拟机管理器的软件,由后者构造出可运行多种操作系统的虚拟机。国外多家公司和大学已对嵌入式虚拟化技术展开研究。嵌入式虚拟化的好处包括减少嵌入式系统开发成本、缩短产品上市周期、利于整合功能、减少功耗、软件资产保值和增强安全性与可靠性。嵌入式虚拟化技术面临的问题包括实时调度问题、嵌入式硬件平台多样性问题、电源管理问题以及跨虚拟机通信问题。嵌入式虚拟化技术将给嵌入式领域带来重大变化,值得关注。     

Data-driven testing methodology for RFID systems

A radio-frequency identification (RFID) system including hardware and software may be updated from time to time after first time deployment. To ensure the reliability of the system, extensive tests are required. However, enumerating all test cases is infeasible, especially when the tests involve time-consuming hardware operations. To solve this problem, we propose a testing methodology for RFID systems which does not enumerate all test cases but rather those which are representative. A clustering method is adopted in selecting representative test cases. Although a small number of selected test cases are run, we can still obtain a relatively high bug detection rate compared with running the enumerated test cases. Our extensive experiments show the efficiency and effectiveness of our testing methodology.     

An RFID Attacker Behavior Taxonomy

A taxonomy of system attacker behavior reveals security vulnerabilities in RFID authorization and monitoring systems. RFID systems are classified by their informational goals-typically, authorization and monitoring. Authorization systems replace the more traditional approaches of granting an entity access to a particular zone, whereas monitoring systems establish an entity's location in that zone. Although their informational goals differ, the underlying hardware is identical for both types of systems; consequently, attacks at the hardware level are the same. However, because attacker behavior invalidates each subsystem's informational goals differently, RFID security requirements should consider these goals individually.     

Detecting component changes at run time with behavior models

Modern software systems are composed of several services which may be developed and maintained by third parties and thus they can change independently and without notice during the system’s runtime execution. In such systems, changes may possibly be a threat to system functional correctness, and thus to its reliability. Hence, it is important to detect them as soon as they happen to enable proper reaction. Change detection can be done by monitoring system execution and comparing the observed execution traces against models of the services composing the application. Unfortunately, formal specifications for services are not usually provided and developers have to infer them. In this paper we propose a methodology which exactly addresses these issues by using software behavior models to monitor component execution and detect changes. In particular, we describe a technique to infer behavior model specifications with a dynamic black box approach, keep them up-to-date with run time observations and detect behavior changes. Finally, we present a case study to validate the effectiveness of the approach in component change detection for a component that implements a complex, real communication protocol.     

一种基于SMS的智能家居远程监控系统

详细描述了一种基于SMS（短消息服务）和Atmega128单片机的智能家居远程监控系统的组成、工作原理及其软、硬件设计。该系统通过手机短信不但可以遥控家居的电器设备,而且还可以对家居安防系统进行远程监视,具有结构简单、运行稳定可靠、成本低和易于推广等特点。     

A modelling-based methodology for evaluating the performance of a real-time embedded control system

This paper presents a modelling-based methodology for embedded control system (ECS) design. Here, instead of developing a new methodology for ECS design, we propose to upgrade an existing one by bridging it with a methodology used in other areas of embedded systems design. We created a transformation bridge between the control-scheduling and the hardware/software (HW/SW) co-design tools. By defining this bridge, we allow for an automatic model transformation. As a result, we obtain more accurate timing-behaviour simulations, considering not only the real-time software, but also the hardware architecture’s impact on the control performance. We show an example with different model-evaluation results compared to real implementation measurements, which clearly demonstrates the benefits of our approach.     

并行和分布式计算机监测系统的实现原理

通用分布式监测系统ＭＳ－１是一种面向并行和分布式计算机系统而设计的行为监测和分析系统。它基于事件驱动的监测原理，并采用软硬件混合实现方式和扩充插 ＰＣ机联网的分布式结构。     

A hybrid monitor for behavior and performance analysis ofdistributed systems

The authors describe a hybrid monitor for measuring the performance and observing the behavior of distributed systems during execution. They emphasize data collection, analysis and presentation of execution data. A special hardware support, which consists of a test and measurement processor (TMP), was designed and has been implemented in the nodes of experimental multicomputer system consisting of eleven nodes. The operations of the TMP are completely transparent with a minimal, less than 0.1%, overhead to the measured system. In the experimental system, all the TMPs were connected with a central monitoring station, using an independent communication network, in order to provide a global view of the monitored system. The central monitoring station displayed the resulting information in easy-to-read charts and graphs. Experience with the TMP shows that it promotes an improved understanding of run-time behavior and performance measurements, which aids in deriving qualitative and quantitative assessments of distributed systems     

Software congestion, mobile servers, and the hyperbolic model

The phenomenon of software congestion is examined. The term refers to situations in which the performance bottleneck of a system is an element of software, rather than a hardware device. Software congestion can occur in any system which contains one or more elements of software whose services may be simultaneously desired by multiple clients, but which can service only one client at a time. It is shown that the use of models which ignore software congestion can produce results that are completely irrelevant to actual system behavior. Furthermore, software congestion is frequently invisible to conventional performance measurement tools. A notational scheme, called mobile servers representation, is introduced for describing those systems in which software congestion may be important. An approximate analytical model, called the hyperbolic model, is developed for analyzing systems with software congestion