Pub Date : 2003-10-01DOI: 10.1109/WORDS.2003.1267484
B. Thuraisingham
This paper provides some directions for developing infrastructures and data managers for dependable sensor networks. By dependable systems we mean systems that adapt to the environment and are secure, fault tolerant and process data in real-time as needed. We start with a discussion of the need for dependable sensor information management and then provide an overview of dependable infrastructures and data managers for such networks. We also discuss some security issues for sensor information management. Finally some directions for further research are given.
{"title":"Dependable Infrastructures and Data Managers for Sensor Networks","authors":"B. Thuraisingham","doi":"10.1109/WORDS.2003.1267484","DOIUrl":"https://doi.org/10.1109/WORDS.2003.1267484","url":null,"abstract":"This paper provides some directions for developing infrastructures and data managers for dependable sensor networks. By dependable systems we mean systems that adapt to the environment and are secure, fault tolerant and process data in real-time as needed. We start with a discussion of the need for dependable sensor information management and then provide an overview of dependable infrastructures and data managers for such networks. We also discuss some security issues for sensor information management. Finally some directions for further research are given.","PeriodicalId":350761,"journal":{"name":"2003 The Ninth IEEE International Workshop on Object-Oriented Real-Time Dependable Systems","volume":"461 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132995782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-01DOI: 10.1109/WORDS.2003.1267531
L. Simoncini
This paper presents the author’s view of the gaps, the challenges and the potentials that exist today when dealing with terms like dependability, trustworthiness, confidence etc. applied to computerized systems and in particular to complex distributed infrastructures and/or services, in contexts where it is no more possible to cope only with accidental faults. Both the "architecture" and the "system" have to be reconsidered from many points of view, if we want than our society can move through what is called "ambient intelligence" to reach what we would like to see, that is "ambient dependability".
{"title":"Architectural Challenges for \"Ambient Dependability\"","authors":"L. Simoncini","doi":"10.1109/WORDS.2003.1267531","DOIUrl":"https://doi.org/10.1109/WORDS.2003.1267531","url":null,"abstract":"This paper presents the author’s view of the gaps, the challenges and the potentials that exist today when dealing with terms like dependability, trustworthiness, confidence etc. applied to computerized systems and in particular to complex distributed infrastructures and/or services, in contexts where it is no more possible to cope only with accidental faults. Both the \"architecture\" and the \"system\" have to be reconsidered from many points of view, if we want than our society can move through what is called \"ambient intelligence\" to reach what we would like to see, that is \"ambient dependability\".","PeriodicalId":350761,"journal":{"name":"2003 The Ninth IEEE International Workshop on Object-Oriented Real-Time Dependable Systems","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121349823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-01DOI: 10.1109/WORDS.2003.1267495
A. Cilardo, Domenico Cotroneo, C. D. Flora, A. Mazzeo, L. Romano, S. Russo
Technology evolution in wireless communication is enabling pervasive connectivity to Internet scale systems. In this scenario, security critical applications are being deployed over platforms which include mobile devices. It is thus key that security services be provided to mobile devices as well. Since security functions are typically based on computationally intensive cryptographic algorithms, achieving this goal is none of a simple task, for the following characteristics of mobile devices: 1) limited computing power, and 2) constraints imposed by peculiarities of the software platforms. This work presents an architecture which allows the provision of digital Time-Stamping services to mobile devices with limited resources. The architecture is described with respect to a case study system.
{"title":"Providing Digital Time Stamping Services to Mobile Devices","authors":"A. Cilardo, Domenico Cotroneo, C. D. Flora, A. Mazzeo, L. Romano, S. Russo","doi":"10.1109/WORDS.2003.1267495","DOIUrl":"https://doi.org/10.1109/WORDS.2003.1267495","url":null,"abstract":"Technology evolution in wireless communication is enabling pervasive connectivity to Internet scale systems. In this scenario, security critical applications are being deployed over platforms which include mobile devices. It is thus key that security services be provided to mobile devices as well. Since security functions are typically based on computationally intensive cryptographic algorithms, achieving this goal is none of a simple task, for the following characteristics of mobile devices: 1) limited computing power, and 2) constraints imposed by peculiarities of the software platforms. This work presents an architecture which allows the provision of digital Time-Stamping services to mobile devices with limited resources. The architecture is described with respect to a case study system.","PeriodicalId":350761,"journal":{"name":"2003 The Ninth IEEE International Workshop on Object-Oriented Real-Time Dependable Systems","volume":"150 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115893161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-01DOI: 10.1109/WORDS.2003.1267552
A. Amendola, R. Maio, M. L. Iacobuzio, F. Poli, Fernando Scalabrini
Demonstrating the safety of modern Railway Control Systems based on microprocessors is more complicated than showing that of traditional relay systems, because the behaviour of microprocessors when faults occur is unpredictable. This paper presents an overview of the main Verification and Validation (V&V) methods used by the Reliability, Availability, Maintainability and Safety (RAMS) team at Ansaldo Segnalamento Ferroviario: how we specify and demonstrate that the system under testing is Reliable, Available, Maintainable and Safe in compliance with the European Railway Standard CENELEC. Tests are executed on a system prototype with an environment simulator and consist of Code Inspection, monitoring I/O Variables, measuring performances by means of a Logic Analyzer, and exercising the diagnostics via a proprietary Fault Injection Board. For critical parts, formal specifications are used (e.g., in SDL).
{"title":"Lessons Learned in Designing and Evaluating Railway Control Systems","authors":"A. Amendola, R. Maio, M. L. Iacobuzio, F. Poli, Fernando Scalabrini","doi":"10.1109/WORDS.2003.1267552","DOIUrl":"https://doi.org/10.1109/WORDS.2003.1267552","url":null,"abstract":"Demonstrating the safety of modern Railway Control Systems based on microprocessors is more complicated than showing that of traditional relay systems, because the behaviour of microprocessors when faults occur is unpredictable. This paper presents an overview of the main Verification and Validation (V&V) methods used by the Reliability, Availability, Maintainability and Safety (RAMS) team at Ansaldo Segnalamento Ferroviario: how we specify and demonstrate that the system under testing is Reliable, Available, Maintainable and Safe in compliance with the European Railway Standard CENELEC. Tests are executed on a system prototype with an environment simulator and consist of Code Inspection, monitoring I/O Variables, measuring performances by means of a Logic Analyzer, and exercising the diagnostics via a proprietary Fault Injection Board. For critical parts, formal specifications are used (e.g., in SDL).","PeriodicalId":350761,"journal":{"name":"2003 The Ninth IEEE International Workshop on Object-Oriented Real-Time Dependable Systems","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132992943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-01DOI: 10.1109/WORDS.2003.1267538
C. Gill
As mission-critical distributed real-time and embedded systems have become more prevalent and are increasingly developed and deployed using an open-systems model, their potential exposure to adversarial attack has increased as well. Furthermore, real-time constraints in such systems add further vulnerabilities to attack, where an adversary need only interfere with the timing of events in a system, rather than having to modify the events themselves. To address this challenge, it is necessary to examine fundamental relationships between real-time and security properties, and to provide a system infrastructure framework designed to mitigate or even avoid the consequences of adversarial attack in real-time systems. This paper makes two main contributions to the state of the art in security for real-time systems. First, it describes particular vulnerabilities of real-time systems to denial-of-service attacks, and categorizes those attacks according to the kind of attack and the mechanisms it affects. Second, it describes the design of RT-POD, a middleware framework for mitigation and possible avoidance of real-time failures in the face of denial of service attacks.
{"title":"RT-POD: A Framework for Real-Time Systems Participation in Own Defense","authors":"C. Gill","doi":"10.1109/WORDS.2003.1267538","DOIUrl":"https://doi.org/10.1109/WORDS.2003.1267538","url":null,"abstract":"As mission-critical distributed real-time and embedded systems have become more prevalent and are increasingly developed and deployed using an open-systems model, their potential exposure to adversarial attack has increased as well. Furthermore, real-time constraints in such systems add further vulnerabilities to attack, where an adversary need only interfere with the timing of events in a system, rather than having to modify the events themselves. To address this challenge, it is necessary to examine fundamental relationships between real-time and security properties, and to provide a system infrastructure framework designed to mitigate or even avoid the consequences of adversarial attack in real-time systems. This paper makes two main contributions to the state of the art in security for real-time systems. First, it describes particular vulnerabilities of real-time systems to denial-of-service attacks, and categorizes those attacks according to the kind of attack and the mechanisms it affects. Second, it describes the design of RT-POD, a middleware framework for mitigation and possible avoidance of real-time failures in the face of denial of service attacks.","PeriodicalId":350761,"journal":{"name":"2003 The Ninth IEEE International Workshop on Object-Oriented Real-Time Dependable Systems","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133334045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-01DOI: 10.1109/WORDS.2003.1267486
H. Kopetz, N. Suri
When trying to find solutions in a problem domain it is a rational step to first explore the limits of the design space. If, during such an endeavor, an impossibility result is encountered, then the further search space can be selectively scoped for solutions to avoid dead-end avenues. With such a perspective, it is the objective of this contribution to outline and discuss the limits of the precise specification of component interfaces in component-based computing systems. Our interest lies in ascertaining limits covers issues of functional composition and verification. Equally importantly, we provide a rationale behind the causes of the limits and impossibility conditions.
{"title":"On the limits of the precise specification of component interfaces","authors":"H. Kopetz, N. Suri","doi":"10.1109/WORDS.2003.1267486","DOIUrl":"https://doi.org/10.1109/WORDS.2003.1267486","url":null,"abstract":"When trying to find solutions in a problem domain it is a rational step to first explore the limits of the design space. If, during such an endeavor, an impossibility result is encountered, then the further search space can be selectively scoped for solutions to avoid dead-end avenues. With such a perspective, it is the objective of this contribution to outline and discuss the limits of the precise specification of component interfaces in component-based computing systems. Our interest lies in ascertaining limits covers issues of functional composition and verification. Equally importantly, we provide a rationale behind the causes of the limits and impossibility conditions.","PeriodicalId":350761,"journal":{"name":"2003 The Ninth IEEE International Workshop on Object-Oriented Real-Time Dependable Systems","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127410167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-01DOI: 10.1109/WORDS.2003.1267497
A. Coccoli, A. Bondavalli
Fault and Error latency have a great impact on the dependability properties of control systems for critical applications. The replication techniques that are used to build such systems and the degree of replication usually are tailored to the tolerance of one fault (at a time) and result inadequate to cope with latent errors that show up altogether. For this reason, internal error detection mechanisms are coupled with on-line testing activities (diagnostic tests) intended to stress each component of the system so to induce errors and thus to anticipate their detection (reducing latency). Different testing strategies can be adopted on the basis of the element to be tested, the fault to be ‘hunted’, the characteristics of the system it is applied to. In this work we start from this simple consideration and will elaborate on architectural organizations to ensure safe and available service.
{"title":"Analysis of Safety Related Architectures","authors":"A. Coccoli, A. Bondavalli","doi":"10.1109/WORDS.2003.1267497","DOIUrl":"https://doi.org/10.1109/WORDS.2003.1267497","url":null,"abstract":"Fault and Error latency have a great impact on the dependability properties of control systems for critical applications. The replication techniques that are used to build such systems and the degree of replication usually are tailored to the tolerance of one fault (at a time) and result inadequate to cope with latent errors that show up altogether. For this reason, internal error detection mechanisms are coupled with on-line testing activities (diagnostic tests) intended to stress each component of the system so to induce errors and thus to anticipate their detection (reducing latency). Different testing strategies can be adopted on the basis of the element to be tested, the fault to be ‘hunted’, the characteristics of the system it is applied to. In this work we start from this simple consideration and will elaborate on architectural organizations to ensure safe and available service.","PeriodicalId":350761,"journal":{"name":"2003 The Ninth IEEE International Workshop on Object-Oriented Real-Time Dependable Systems","volume":"10 38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129289973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-01DOI: 10.1109/WORDS.2003.1267504
N. Looker, Jie Xu
This paper presents our research on devising a dependability assessment method for SOAP-based Web Services using network level fault injection. We compare existing DCE middleware dependability testing research with the requirements of testing SOAP RPC-based applications and derive a new method and fault model for testing web services. From this we have implemented an extendable fault injector framework and undertaken some proof of concept experiments with a system based around Apache SOAP and Apache Tomcat. We also present results from our initial experiments, which uncovered a discrepancy within our system. We finally detail future research, including plans to adapt this fault injector framework from the stateless environment of a standard web service to the stateful environment of an OGSA service.
{"title":"Assessing the Dependability of SOAP RPC-Based Web Services by Fault Injection","authors":"N. Looker, Jie Xu","doi":"10.1109/WORDS.2003.1267504","DOIUrl":"https://doi.org/10.1109/WORDS.2003.1267504","url":null,"abstract":"This paper presents our research on devising a dependability assessment method for SOAP-based Web Services using network level fault injection. We compare existing DCE middleware dependability testing research with the requirements of testing SOAP RPC-based applications and derive a new method and fault model for testing web services. From this we have implemented an extendable fault injector framework and undertaken some proof of concept experiments with a system based around Apache SOAP and Apache Tomcat. We also present results from our initial experiments, which uncovered a discrepancy within our system. We finally detail future research, including plans to adapt this fault injector framework from the stateless environment of a standard web service to the stateful environment of an OGSA service.","PeriodicalId":350761,"journal":{"name":"2003 The Ninth IEEE International Workshop on Object-Oriented Real-Time Dependable Systems","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127721115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-01DOI: 10.1109/WORDS.2003.1267540
P. Bellavista, Antonio Corradi
New challenging service scenarios are integrating wireless portable devices with limited and heterogeneous capabilities. They are expected to access both traditional and novel (context-dependent) Internet services. This not only calls for novel infrastructures to support the integration of mobile devices with the fixed network, but also stresses the necessity of negotiation-time tailoring and provision-time adaptation of Quality of Service (QoS). The paper presents a flexible and dynamic middleware for the management of multimedia QoS to wireless devices that can roam during service provisioning. The middleware exploits mobile agents that act as device shadow proxies over the fixed network to transparently follow the device movements between wireless localities, to negotiate the proper QoS level, and to dynamically adapt multimedia flows depending on device profiles and user preferences. In particular, the paper focuses on how the middleware achieves the on-line visibility of the device change of locality in a portable way over different implementations of different wireless technologies, i.e., IEEE 802.11 and Bluetooth. The first experimental results show that, notwithstanding the application-level approach, the middleware reorganization time is compatible with the requirements imposed by the addressed multimedia scenario.
{"title":"Mobile Middleware Solutions for the Adaptive Management of Multimedia QoS to Wireless Portable Devices","authors":"P. Bellavista, Antonio Corradi","doi":"10.1109/WORDS.2003.1267540","DOIUrl":"https://doi.org/10.1109/WORDS.2003.1267540","url":null,"abstract":"New challenging service scenarios are integrating wireless portable devices with limited and heterogeneous capabilities. They are expected to access both traditional and novel (context-dependent) Internet services. This not only calls for novel infrastructures to support the integration of mobile devices with the fixed network, but also stresses the necessity of negotiation-time tailoring and provision-time adaptation of Quality of Service (QoS). The paper presents a flexible and dynamic middleware for the management of multimedia QoS to wireless devices that can roam during service provisioning. The middleware exploits mobile agents that act as device shadow proxies over the fixed network to transparently follow the device movements between wireless localities, to negotiate the proper QoS level, and to dynamically adapt multimedia flows depending on device profiles and user preferences. In particular, the paper focuses on how the middleware achieves the on-line visibility of the device change of locality in a portable way over different implementations of different wireless technologies, i.e., IEEE 802.11 and Bluetooth. The first experimental results show that, notwithstanding the application-level approach, the middleware reorganization time is compatible with the requirements imposed by the addressed multimedia scenario.","PeriodicalId":350761,"journal":{"name":"2003 The Ninth IEEE International Workshop on Object-Oriented Real-Time Dependable Systems","volume":"177 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116860826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-01DOI: 10.1109/WORDS.2003.1267541
Jiyong Park, Saehwa Kim, Seongsoo Hong
Despite of the proliferation of object-oriented and component technology, their application to real-time operating systems (RTOS) has been limited since most design concerns in RTOSes crosscut software components and these are critical to deliver required performance and functionality. Aspect-Oriented Programming (AOP) is a very effective means to solve the crosscutting problem. However, we have observed the following limitations of the current AOP framework: (1) the current text-based AOP languages cannot clearly show how aspects are weaved together, (2) their granularity is too coarse to capture all aspects in an RTOS, (3) it is difficult to control the weaving process, since aspect weavers are usually hard-coded. In this paper, we propose a new AOP framework that provides (1) a graphical aspect programming environment that visualizes aspects, crosscutting classes, and method structures, (2) a new aspect model that supports a sub-method level granularity where an aspect is defined as a set of classes, and (3) an aspect weaving process specified by an object-oriented meta-model transformation. Since our aspect-oriented programming framework improves the expressiveness of the crosscutting concerns of RTOSes and automates aspect weaver generation, it can enhance RTOS customization.
{"title":"Weaving Aspects into Real-Time Operating System Design Using Object-Oriented Model Transformation","authors":"Jiyong Park, Saehwa Kim, Seongsoo Hong","doi":"10.1109/WORDS.2003.1267541","DOIUrl":"https://doi.org/10.1109/WORDS.2003.1267541","url":null,"abstract":"Despite of the proliferation of object-oriented and component technology, their application to real-time operating systems (RTOS) has been limited since most design concerns in RTOSes crosscut software components and these are critical to deliver required performance and functionality. Aspect-Oriented Programming (AOP) is a very effective means to solve the crosscutting problem. However, we have observed the following limitations of the current AOP framework: (1) the current text-based AOP languages cannot clearly show how aspects are weaved together, (2) their granularity is too coarse to capture all aspects in an RTOS, (3) it is difficult to control the weaving process, since aspect weavers are usually hard-coded. In this paper, we propose a new AOP framework that provides (1) a graphical aspect programming environment that visualizes aspects, crosscutting classes, and method structures, (2) a new aspect model that supports a sub-method level granularity where an aspect is defined as a set of classes, and (3) an aspect weaving process specified by an object-oriented meta-model transformation. Since our aspect-oriented programming framework improves the expressiveness of the crosscutting concerns of RTOSes and automates aspect weaver generation, it can enhance RTOS customization.","PeriodicalId":350761,"journal":{"name":"2003 The Ninth IEEE International Workshop on Object-Oriented Real-Time Dependable Systems","volume":"391 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123959619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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