Michael Barth, Jonghun Yoo, Saehwa Kim, Seongsoo Hong
The software communications architecture (SCA), which has been adopted as an SDR (software defined radio) Forum standard, provides a framework that successfully exploits common design patterns of distributed, real-time, and object-oriented embedded systems software. We have fully implemented the SCA v2.2 in C++. During this implementation process, we have encountered the lack of a suitable design pattern for releasing the SCA applications. Unfortunately, design patterns for releasing objects have been neither extensively addressed nor well investigated as opposed to creational design patterns. This is largely due to the fact that such releasing design patterns are highly dependent on programming languages. In this paper, we investigate three viable design patterns for releasing the SCA applications in C++ and discuss their pros and cons. In addition, we select the most portable and thus most reusable pattern, which we name Vulture design pattern, among those alternatives and detail our specific implementation
{"title":"Design patterns for releasing applications in C++ implementations of JTRS software communications architecture","authors":"Michael Barth, Jonghun Yoo, Saehwa Kim, Seongsoo Hong","doi":"10.1109/ISORC.2006.29","DOIUrl":"https://doi.org/10.1109/ISORC.2006.29","url":null,"abstract":"The software communications architecture (SCA), which has been adopted as an SDR (software defined radio) Forum standard, provides a framework that successfully exploits common design patterns of distributed, real-time, and object-oriented embedded systems software. We have fully implemented the SCA v2.2 in C++. During this implementation process, we have encountered the lack of a suitable design pattern for releasing the SCA applications. Unfortunately, design patterns for releasing objects have been neither extensively addressed nor well investigated as opposed to creational design patterns. This is largely due to the fact that such releasing design patterns are highly dependent on programming languages. In this paper, we investigate three viable design patterns for releasing the SCA applications in C++ and discuss their pros and cons. In addition, we select the most portable and thus most reusable pattern, which we name Vulture design pattern, among those alternatives and detail our specific implementation","PeriodicalId":212174,"journal":{"name":"Ninth IEEE International Symposium on Object and Component-Oriented Real-Time Distributed Computing (ISORC'06)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123546286","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}
In the development of embedded systems, higher-level programming languages have become popular because they often induce higher developer productivity. Tool developers desiring to offer support for such languages need to solve various problems; in particular, they need to support the creation of realtime systems. In this paper, we present an approach for supporting real-time capabilities in C# and, consequently, the Common Language Infrastructure
{"title":"Towards a real-time implementation of the ECMA Common Language Infrastructure","authors":"M. V. Löwis, A. Rasche","doi":"10.1109/ISORC.2006.72","DOIUrl":"https://doi.org/10.1109/ISORC.2006.72","url":null,"abstract":"In the development of embedded systems, higher-level programming languages have become popular because they often induce higher developer productivity. Tool developers desiring to offer support for such languages need to solve various problems; in particular, they need to support the creation of realtime systems. In this paper, we present an approach for supporting real-time capabilities in C# and, consequently, the Common Language Infrastructure","PeriodicalId":212174,"journal":{"name":"Ninth IEEE International Symposium on Object and Component-Oriented Real-Time Distributed Computing (ISORC'06)","volume":"151 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115560115","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}
P. Watson, C. Fowler, Charles Kubicek, A. Mukherjee, J. Colquhoun, M. Hewitt, Savas Parastatidis
Dynasoar is an infrastructure for dynamically deploying Web services over a grid or the Internet. It enables an approach to grid computing in which distributed applications are built around services instead of jobs. Dynasoar automatically deploys a service on an available host if no existing deployments exist, or if performance requirements cannot be met by existing deployments. This is analogous to remote job scheduling, but offers the opportunity for improved performance as the cost of moving and deploying the service can be shared across the processing of many messages. A key feature of the architecture is that it makes a clear separation between Web service providers, who offer services to consumers, and host providers, who offer computational resources on which services can be deployed, and messages sent to them processed. Separating these two components and defining their interactions, opens up the opportunity for interesting new organisational/business models
{"title":"Dynamically deploying Web services on a grid using Dynasoar","authors":"P. Watson, C. Fowler, Charles Kubicek, A. Mukherjee, J. Colquhoun, M. Hewitt, Savas Parastatidis","doi":"10.1109/ISORC.2006.32","DOIUrl":"https://doi.org/10.1109/ISORC.2006.32","url":null,"abstract":"Dynasoar is an infrastructure for dynamically deploying Web services over a grid or the Internet. It enables an approach to grid computing in which distributed applications are built around services instead of jobs. Dynasoar automatically deploys a service on an available host if no existing deployments exist, or if performance requirements cannot be met by existing deployments. This is analogous to remote job scheduling, but offers the opportunity for improved performance as the cost of moving and deploying the service can be shared across the processing of many messages. A key feature of the architecture is that it makes a clear separation between Web service providers, who offer services to consumers, and host providers, who offer computational resources on which services can be deployed, and messages sent to them processed. Separating these two components and defining their interactions, opens up the opportunity for interesting new organisational/business models","PeriodicalId":212174,"journal":{"name":"Ninth IEEE International Symposium on Object and Component-Oriented Real-Time Distributed Computing (ISORC'06)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128425170","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}
O. Goh, Yann-Hang Lee, Ziad Kaakani, Elliott Rachlin
We present a schedulable garbage collection for realtime applications in virtual machine environments. The design objective is to make the pause time caused by garbage collection operations controllable, and the invocation of garbage collection predictable. Thus, real-time applications can be schedulable along with garbage collection. We develop a prototype for a schedulable garbage collection in MONO CLI execution environment. A cost model of garbage collection is established based on measured WCET to predict the execution time and overhead of garbage collection operations. A scheduling algorithm of garbage collection and application tasks is presented to illustrate how the time and memory constraints of real-time systems can be met. The experiment result of the scheduling algorithm for a periodic task set on the prototype is included in the paper
{"title":"Integrated scheduling with garbage collection for real-time embedded applications in CLI","authors":"O. Goh, Yann-Hang Lee, Ziad Kaakani, Elliott Rachlin","doi":"10.1109/ISORC.2006.41","DOIUrl":"https://doi.org/10.1109/ISORC.2006.41","url":null,"abstract":"We present a schedulable garbage collection for realtime applications in virtual machine environments. The design objective is to make the pause time caused by garbage collection operations controllable, and the invocation of garbage collection predictable. Thus, real-time applications can be schedulable along with garbage collection. We develop a prototype for a schedulable garbage collection in MONO CLI execution environment. A cost model of garbage collection is established based on measured WCET to predict the execution time and overhead of garbage collection operations. A scheduling algorithm of garbage collection and application tasks is presented to illustrate how the time and memory constraints of real-time systems can be met. The experiment result of the scheduling algorithm for a periodic task set on the prototype is included in the paper","PeriodicalId":212174,"journal":{"name":"Ninth IEEE International Symposium on Object and Component-Oriented Real-Time Distributed Computing (ISORC'06)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123657213","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}
L. Lung, F. Favarim, Giuliana Teixeira Santos, M. Correia
The fault tolerance provided by FT-CORBA is basically static, that is, once the fault tolerance properties of a group of replicated processes are defined, they cannot be modified in runtime. A support for dynamic reconfiguration of the replication would be highly advantageous since it would allow the implementation of mechanisms for adaptive fault tolerance, enabling FT-CORBA to adapt to the changes that can occur in the execution environment. In this paper, we propose a set of extensions to the FT-CORBA infrastructure in the form of interfaces and object service implementations, enabling it to support dynamic reconfiguration of the replication
{"title":"An infrastructure for adaptive fault tolerance on FT-CORBA","authors":"L. Lung, F. Favarim, Giuliana Teixeira Santos, M. Correia","doi":"10.1109/ISORC.2006.16","DOIUrl":"https://doi.org/10.1109/ISORC.2006.16","url":null,"abstract":"The fault tolerance provided by FT-CORBA is basically static, that is, once the fault tolerance properties of a group of replicated processes are defined, they cannot be modified in runtime. A support for dynamic reconfiguration of the replication would be highly advantageous since it would allow the implementation of mechanisms for adaptive fault tolerance, enabling FT-CORBA to adapt to the changes that can occur in the execution environment. In this paper, we propose a set of extensions to the FT-CORBA infrastructure in the form of interfaces and object service implementations, enabling it to support dynamic reconfiguration of the replication","PeriodicalId":212174,"journal":{"name":"Ninth IEEE International Symposium on Object and Component-Oriented Real-Time Distributed Computing (ISORC'06)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133873975","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}
The network connectivity is a basic requirement while implementing fundamental communication and storage abstractions in P2P networks, featuring scalability and fault-tolerance. The quality of services of abstractions like for example multicast, publish/subscribe, group membership or persistent storage is strongly related to the connectivity degree of the underlying overlay. Intuitively, a higher overlay connectivity ensures a reinforced reliability and consequently, the deployment of distributed applications with real-time constraints on top of these overlays becomes feasible even in environments characterized by a high dynamicity, i.e., nodes arriving and departing at a high rate. Our paper proposes a novel delta-connected DHT-free P2P overlay. Our overlay offers strong connectivity guarantees despite the system dynamicity. The construction and the maintenance of our overlay is completely decentralized and handled strictly locally, through deterministic algorithms whose correctness is rigorously proved
{"title":"Deterministic /spl delta/-connected overlay for peer-to-peer networks","authors":"A. Datta, M. Potop-Butucaru, A. Virgillito","doi":"10.1109/ISORC.2006.30","DOIUrl":"https://doi.org/10.1109/ISORC.2006.30","url":null,"abstract":"The network connectivity is a basic requirement while implementing fundamental communication and storage abstractions in P2P networks, featuring scalability and fault-tolerance. The quality of services of abstractions like for example multicast, publish/subscribe, group membership or persistent storage is strongly related to the connectivity degree of the underlying overlay. Intuitively, a higher overlay connectivity ensures a reinforced reliability and consequently, the deployment of distributed applications with real-time constraints on top of these overlays becomes feasible even in environments characterized by a high dynamicity, i.e., nodes arriving and departing at a high rate. Our paper proposes a novel delta-connected DHT-free P2P overlay. Our overlay offers strong connectivity guarantees despite the system dynamicity. The construction and the maintenance of our overlay is completely decentralized and handled strictly locally, through deterministic algorithms whose correctness is rigorously proved","PeriodicalId":212174,"journal":{"name":"Ninth IEEE International Symposium on Object and Component-Oriented Real-Time Distributed Computing (ISORC'06)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133353438","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}
Mathias Pacher, Alexander von Renteln, U. Brinkschulte
This paper presents the architecture and conception of an organic middleware based on the yet existing, not organic middleware OSA+. We show new general design principles helping to establish the self-organizing middleware which can be used for totally different applications like robotics, warehouse management and the planning of a person's daily routine
{"title":"Towards an organic middleware for real-time applications","authors":"Mathias Pacher, Alexander von Renteln, U. Brinkschulte","doi":"10.1109/ISORC.2006.73","DOIUrl":"https://doi.org/10.1109/ISORC.2006.73","url":null,"abstract":"This paper presents the architecture and conception of an organic middleware based on the yet existing, not organic middleware OSA+. We show new general design principles helping to establish the self-organizing middleware which can be used for totally different applications like robotics, warehouse management and the planning of a person's daily routine","PeriodicalId":212174,"journal":{"name":"Ninth IEEE International Symposium on Object and Component-Oriented Real-Time Distributed Computing (ISORC'06)","volume":"762 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117012128","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}
In a real-time distributed computing 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 distributed object computing 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-time distributed environment
{"title":"Dependable and secure TMO scheme","authors":"Jungin Kim, B. Thuraisingham","doi":"10.1109/ISORC.2006.27","DOIUrl":"https://doi.org/10.1109/ISORC.2006.27","url":null,"abstract":"In a real-time distributed computing 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 distributed object computing 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-time distributed environment","PeriodicalId":212174,"journal":{"name":"Ninth IEEE International Symposium on Object and Component-Oriented Real-Time Distributed Computing (ISORC'06)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129700112","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}
In this paper we show how to take into account kernel overheads in classical real-time feasibility conditions for fixed priority (FP) scheduling where tasks having the same fixed priority are scheduled FP/FIFO. We consider the periodic task model with arbitrary deadlines and an event driven OSEK kernel. The feasibility conditions are based on the worst case response time computation of the tasks. We identify the sources of kernel overheads that influence the response time of the tasks. In such a system the overheads are due to the context switching that activates/terminates and reschedules tasks and to the granularity of the periodic timer used to implement the periodic task model. We show how to take into account those overheads in the classical FP/FIFO feasibility conditions. We compare the worst case response time obtained with kernel overhead to the response time obtained on a real event driven OSEK implementation. We show that the kernel overheads cannot be neglected and that the theoretical results are valid and can be used for a real-time dimensioning
{"title":"FP/FIFO feasibility conditions with kernel overheads for periodic tasks on an event driven OSEK system","authors":"F. Bimbard, L. George","doi":"10.1109/ISORC.2006.36","DOIUrl":"https://doi.org/10.1109/ISORC.2006.36","url":null,"abstract":"In this paper we show how to take into account kernel overheads in classical real-time feasibility conditions for fixed priority (FP) scheduling where tasks having the same fixed priority are scheduled FP/FIFO. We consider the periodic task model with arbitrary deadlines and an event driven OSEK kernel. The feasibility conditions are based on the worst case response time computation of the tasks. We identify the sources of kernel overheads that influence the response time of the tasks. In such a system the overheads are due to the context switching that activates/terminates and reschedules tasks and to the granularity of the periodic timer used to implement the periodic task model. We show how to take into account those overheads in the classical FP/FIFO feasibility conditions. We compare the worst case response time obtained with kernel overhead to the response time obtained on a real event driven OSEK implementation. We show that the kernel overheads cannot be neglected and that the theoretical results are valid and can be used for a real-time dimensioning","PeriodicalId":212174,"journal":{"name":"Ninth IEEE International Symposium on Object and Component-Oriented Real-Time Distributed Computing (ISORC'06)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127860322","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}
Antonio Di Ferdinando, P. Ezhilchelvan, M. Dales, J. Crowcroft
E-business organizations commonly trade services together with quality of service (QoS) guarantees that are often dynamically agreed upon prior to service provisioning. Violating agreed QoS levels incurs penalties and hence service providers agree to QoS requests only after assessing the resource availability. Thus the system should, in addition to providing the services: (i) monitor resource availability, (ii) assess the affordability of a requested QoS level, and (iii) adapt autonomically to QoS perturbations which might undermine any assumptions made during assessment. This paper will focus on building such a system for reliably multicasting messages of arbitrary size over a loss-prone network of arbitrary topology such as the Internet. The QoS metrics of interest will be reliability, latency and relative latency. We meet the objectives (i)-(iii) by describing a network monitoring scheme, developing two multicast protocols, and by analytically estimating the achievable latencies and reliability in terms of controllable protocol parameters. Protocol development involves extending in two distinct ways an existing QoS-adaptive protocol designed for a single packet. Analytical estimation makes use of experimentally justified approximations and their impact is evaluated through simulations. As the protocol extension approaches are complementary in nature, so are the application contexts they are found best suited to; e.g., one is suited to small messages while the other to large messages
{"title":"A QoS-negotiable middleware system for reliably multicasting messages of arbitrary size","authors":"Antonio Di Ferdinando, P. Ezhilchelvan, M. Dales, J. Crowcroft","doi":"10.1109/ISORC.2006.10","DOIUrl":"https://doi.org/10.1109/ISORC.2006.10","url":null,"abstract":"E-business organizations commonly trade services together with quality of service (QoS) guarantees that are often dynamically agreed upon prior to service provisioning. Violating agreed QoS levels incurs penalties and hence service providers agree to QoS requests only after assessing the resource availability. Thus the system should, in addition to providing the services: (i) monitor resource availability, (ii) assess the affordability of a requested QoS level, and (iii) adapt autonomically to QoS perturbations which might undermine any assumptions made during assessment. This paper will focus on building such a system for reliably multicasting messages of arbitrary size over a loss-prone network of arbitrary topology such as the Internet. The QoS metrics of interest will be reliability, latency and relative latency. We meet the objectives (i)-(iii) by describing a network monitoring scheme, developing two multicast protocols, and by analytically estimating the achievable latencies and reliability in terms of controllable protocol parameters. Protocol development involves extending in two distinct ways an existing QoS-adaptive protocol designed for a single packet. Analytical estimation makes use of experimentally justified approximations and their impact is evaluated through simulations. As the protocol extension approaches are complementary in nature, so are the application contexts they are found best suited to; e.g., one is suited to small messages while the other to large messages","PeriodicalId":212174,"journal":{"name":"Ninth IEEE International Symposium on Object and Component-Oriented Real-Time Distributed Computing (ISORC'06)","volume":"200 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131543425","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：