Pub Date : 1996-05-27DOI: 10.1109/ICDCS.1996.507899
Jun Sun, J. Liu
In many distributed real-time systems, the workload can be modeled as a set of periodic tasks, each of which consists of a chain of subtasks executing on different processors. Synchronization protocols are used to govern the release of subtasks so that the precedence constraints among subtasks are satisfied and the schedulability of the resultant system is analyzable. Tasks have different worst-case and average end-to-end response times when different protocols are used. In this paper, we consider distributed real-time systems with independent, periodic tasks and fixed-priority scheduling algorithms. We propose three synchronization protocols and conduct simulation to compare their performance with respect to the two timing aspects.
{"title":"Synchronization protocols in distributed real-time systems","authors":"Jun Sun, J. Liu","doi":"10.1109/ICDCS.1996.507899","DOIUrl":"https://doi.org/10.1109/ICDCS.1996.507899","url":null,"abstract":"In many distributed real-time systems, the workload can be modeled as a set of periodic tasks, each of which consists of a chain of subtasks executing on different processors. Synchronization protocols are used to govern the release of subtasks so that the precedence constraints among subtasks are satisfied and the schedulability of the resultant system is analyzable. Tasks have different worst-case and average end-to-end response times when different protocols are used. In this paper, we consider distributed real-time systems with independent, periodic tasks and fixed-priority scheduling algorithms. We propose three synchronization protocols and conduct simulation to compare their performance with respect to the two timing aspects.","PeriodicalId":159322,"journal":{"name":"Proceedings of 16th International Conference on Distributed Computing Systems","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122067412","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 : 1996-05-27DOI: 10.1109/ICDCS.1996.508017
P. Danzig, D. DeLucia, K. Obraczka, Erh-Yuan Tsai
This paper reports the design, implementation, and performance of a scalable and efficient tool to replicate Internet information services. Our tool targets replication degrees of tens of thousands of weakly-consistent replicas scattered throughout the Internet's thousands of autonomously administered domains. The main goal of our replication tool is to make existing replication algorithms scale in today's exponentially-growing, autonomously-managed internetworks.
{"title":"A tool for massively replicating Internet archives: design, implementation, and experience","authors":"P. Danzig, D. DeLucia, K. Obraczka, Erh-Yuan Tsai","doi":"10.1109/ICDCS.1996.508017","DOIUrl":"https://doi.org/10.1109/ICDCS.1996.508017","url":null,"abstract":"This paper reports the design, implementation, and performance of a scalable and efficient tool to replicate Internet information services. Our tool targets replication degrees of tens of thousands of weakly-consistent replicas scattered throughout the Internet's thousands of autonomously administered domains. The main goal of our replication tool is to make existing replication algorithms scale in today's exponentially-growing, autonomously-managed internetworks.","PeriodicalId":159322,"journal":{"name":"Proceedings of 16th International Conference on Distributed Computing Systems","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124105280","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 : 1996-05-27DOI: 10.1109/ICDCS.1996.508003
Wolfgang Golubski, D. Lammers, W. Lippe
We present theoretical and empirical investigations to explore the potential of dynamic load balancing for homogeneous systems. We introduce the object-based programming environment MOM. Then we define an own load balancing algorithm called Gating and compare it with other well known algorithms, theoretically, in a simulation and in the MOM system. The obtaining results are discussed.
{"title":"Theoretical and empirical results on dynamic load balancing in an object-based distributed environment","authors":"Wolfgang Golubski, D. Lammers, W. Lippe","doi":"10.1109/ICDCS.1996.508003","DOIUrl":"https://doi.org/10.1109/ICDCS.1996.508003","url":null,"abstract":"We present theoretical and empirical investigations to explore the potential of dynamic load balancing for homogeneous systems. We introduce the object-based programming environment MOM. Then we define an own load balancing algorithm called Gating and compare it with other well known algorithms, theoretically, in a simulation and in the MOM system. The obtaining results are discussed.","PeriodicalId":159322,"journal":{"name":"Proceedings of 16th International Conference on Distributed Computing Systems","volume":"87 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126018744","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 : 1996-05-27DOI: 10.1109/ICDCS.1996.507930
Weidong Chen, E. C. Lin
Mobile hosts in a wireless network can move from one location to another while communicating with other hosts. A challenge is to provide seamless network access for mobile hosts and, at the same time, to retain compatibility with existing network protocols and applications. This paper addresses the issue of route optimization in IP mobility support that provides mobile handoff and "triangle" routing to mobile hosts through their home agents. We combine IP mobility support with hierarchical dynamic routing protocols OSPF and BGP. Existing mechanisms of authentication, incremental route propagation, and address aggregation can be used for efficient and secure propagation of location updates of mobile hosts. The geographical locality of consecutive mobile handoffs fits well with hierarchical dynamic routing protocols. No changes are required on fixed hosts or on routers that do not handle mobile hosts directly.
{"title":"Route optimization and location updates for mobile hosts","authors":"Weidong Chen, E. C. Lin","doi":"10.1109/ICDCS.1996.507930","DOIUrl":"https://doi.org/10.1109/ICDCS.1996.507930","url":null,"abstract":"Mobile hosts in a wireless network can move from one location to another while communicating with other hosts. A challenge is to provide seamless network access for mobile hosts and, at the same time, to retain compatibility with existing network protocols and applications. This paper addresses the issue of route optimization in IP mobility support that provides mobile handoff and \"triangle\" routing to mobile hosts through their home agents. We combine IP mobility support with hierarchical dynamic routing protocols OSPF and BGP. Existing mechanisms of authentication, incremental route propagation, and address aggregation can be used for efficient and secure propagation of location updates of mobile hosts. The geographical locality of consecutive mobile handoffs fits well with hierarchical dynamic routing protocols. No changes are required on fixed hosts or on routers that do not handle mobile hosts directly.","PeriodicalId":159322,"journal":{"name":"Proceedings of 16th International Conference on Distributed Computing Systems","volume":"151 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127286034","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 : 1996-05-27DOI: 10.1109/ICDCS.1996.508029
M. Choy
A token based algorithm for distributed mutual exclusion is presented. It uses a distributed counter to tolerate faults due to site failures and communication failures. This eliminates the need for expensive election protocols that are commonly employed in existing token-based algorithms. As in many existing fault-tolerant mutual exclusion algorithms, timeouts are used to detect failures. Our algorithm has the unique property that even if timeout periods are incorrectly assumed, the safety requirement of mutual exclusion is still guaranteed. It is, therefore, suitable for highly asynchronous distributed environments. Performance analysis shows that the algorithm is also efficient in terms of the average number of messages required per critical section, and the average time delay to enter the critical section. Finally, we show how to obtain a bounded algorithm from the basic unbounded algorithm.
{"title":"Robust distributed mutual exclusion","authors":"M. Choy","doi":"10.1109/ICDCS.1996.508029","DOIUrl":"https://doi.org/10.1109/ICDCS.1996.508029","url":null,"abstract":"A token based algorithm for distributed mutual exclusion is presented. It uses a distributed counter to tolerate faults due to site failures and communication failures. This eliminates the need for expensive election protocols that are commonly employed in existing token-based algorithms. As in many existing fault-tolerant mutual exclusion algorithms, timeouts are used to detect failures. Our algorithm has the unique property that even if timeout periods are incorrectly assumed, the safety requirement of mutual exclusion is still guaranteed. It is, therefore, suitable for highly asynchronous distributed environments. Performance analysis shows that the algorithm is also efficient in terms of the average number of messages required per critical section, and the average time delay to enter the critical section. Finally, we show how to obtain a bounded algorithm from the basic unbounded algorithm.","PeriodicalId":159322,"journal":{"name":"Proceedings of 16th International Conference on Distributed Computing Systems","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127546449","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 : 1996-05-27DOI: 10.1109/ICDCS.1996.507970
Gurdip Singh, Zhenyu Mao
We propose a compositional technique to design multifunction protocols. The technique involves first designing the protocols performing the various functions separately and then combining them using a set of constraints. The constraints are used to specify the interactions between the component protocols. The interactions, for example, specify when a function has to be performed and whether two functions can be performed concurrently or not. We illustrate the use of our technique by designing several protocols. We give sufficient conditions to infer properties of the composite protocol from those of the component protocols.
{"title":"Structured design of communication protocols","authors":"Gurdip Singh, Zhenyu Mao","doi":"10.1109/ICDCS.1996.507970","DOIUrl":"https://doi.org/10.1109/ICDCS.1996.507970","url":null,"abstract":"We propose a compositional technique to design multifunction protocols. The technique involves first designing the protocols performing the various functions separately and then combining them using a set of constraints. The constraints are used to specify the interactions between the component protocols. The interactions, for example, specify when a function has to be performed and whether two functions can be performed concurrently or not. We illustrate the use of our technique by designing several protocols. We give sufficient conditions to infer properties of the composite protocol from those of the component protocols.","PeriodicalId":159322,"journal":{"name":"Proceedings of 16th International Conference on Distributed Computing Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130105059","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 : 1996-05-27DOI: 10.1109/ICDCS.1996.508019
Chung-Min Chen, K. Salem, M. Livny
We present the Distributed Batch Controller (DBC), a system built to support batch processing of large scientific datasets. The DBC implements a federation of autonomous workstation pools, which may be widely distributed. Individual batch jobs are executed using idle workstations in these pools. Input data are staged to the pool before processing begins. We describe the architecture and implementation of the DBC, and present the results of experiments in which it is used to perform image compression.
{"title":"The DEC: processing scientific data over the Internet","authors":"Chung-Min Chen, K. Salem, M. Livny","doi":"10.1109/ICDCS.1996.508019","DOIUrl":"https://doi.org/10.1109/ICDCS.1996.508019","url":null,"abstract":"We present the Distributed Batch Controller (DBC), a system built to support batch processing of large scientific datasets. The DBC implements a federation of autonomous workstation pools, which may be widely distributed. Individual batch jobs are executed using idle workstations in these pools. Input data are staged to the pool before processing begins. We describe the architecture and implementation of the DBC, and present the results of experiments in which it is used to perform image compression.","PeriodicalId":159322,"journal":{"name":"Proceedings of 16th International Conference on Distributed Computing Systems","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131716724","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 : 1996-05-27DOI: 10.1109/ICDCS.1996.507997
Crispin Cowan, H. Lutfiyya
Optimism is a powerful technique for avoiding latency by increasing concurrency. Optimistically assuming the results of one computation allows other computations to execute in parallel, even when they depend on the assumed result. Optimistic techniques can particularly benefit distributed systems because of the critical impact of communications latency. This paper reviews HOPE: our model of optimistic programming, and describes how optimism can enhance distributed program performance by avoiding remote communications delay. We then present the wait-free algorithm used to implement HOPE in a distributed environment.
{"title":"A wait-free algorithm for optimistic programming: HOPE realized","authors":"Crispin Cowan, H. Lutfiyya","doi":"10.1109/ICDCS.1996.507997","DOIUrl":"https://doi.org/10.1109/ICDCS.1996.507997","url":null,"abstract":"Optimism is a powerful technique for avoiding latency by increasing concurrency. Optimistically assuming the results of one computation allows other computations to execute in parallel, even when they depend on the assumed result. Optimistic techniques can particularly benefit distributed systems because of the critical impact of communications latency. This paper reviews HOPE: our model of optimistic programming, and describes how optimism can enhance distributed program performance by avoiding remote communications delay. We then present the wait-free algorithm used to implement HOPE in a distributed environment.","PeriodicalId":159322,"journal":{"name":"Proceedings of 16th International Conference on Distributed Computing Systems","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125265484","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 : 1996-05-27DOI: 10.1109/ICDCS.1996.507917
S. Singhal, D. Cheriton
Distributed interactive simulation systems are growing to include well over 100,000 dynamic entities for applications such as multiplayer video games, military and industrial training, and collaborative engineering. In these applications, each host receives updates (such as position and orientation) from remote entities, models and renders the scene, and performs other tasks such as collision detection. The number of entities places a heavy burden on both the networking resources and computational resources available to the application. To address these limitations, some systems have aggregated information about groups of simulation entities according to their organizational structure or their location within the virtual world. However traditional aggregation techniques are inadequate because remote hosts need to access entities based on both their organization and their virtual world position. This paper describes projection aggregations, a technique for grouping entities by both their organization and location. Remote hosts use projections to control which entities are represented locally and at what level-of-detail. We describe how projection aggregations are implemented in a networked environment and demonstrate how they reduce network bandwidth and computational requirements. Finally, we argue that projection aggregations represent a general-purpose framework for representing all simulation entities, thereby supporting evolution of entity models.
{"title":"Using projection aggregations to support scalability in distributed simulation","authors":"S. Singhal, D. Cheriton","doi":"10.1109/ICDCS.1996.507917","DOIUrl":"https://doi.org/10.1109/ICDCS.1996.507917","url":null,"abstract":"Distributed interactive simulation systems are growing to include well over 100,000 dynamic entities for applications such as multiplayer video games, military and industrial training, and collaborative engineering. In these applications, each host receives updates (such as position and orientation) from remote entities, models and renders the scene, and performs other tasks such as collision detection. The number of entities places a heavy burden on both the networking resources and computational resources available to the application. To address these limitations, some systems have aggregated information about groups of simulation entities according to their organizational structure or their location within the virtual world. However traditional aggregation techniques are inadequate because remote hosts need to access entities based on both their organization and their virtual world position. This paper describes projection aggregations, a technique for grouping entities by both their organization and location. Remote hosts use projections to control which entities are represented locally and at what level-of-detail. We describe how projection aggregations are implemented in a networked environment and demonstrate how they reduce network bandwidth and computational requirements. Finally, we argue that projection aggregations represent a general-purpose framework for representing all simulation entities, thereby supporting evolution of entity models.","PeriodicalId":159322,"journal":{"name":"Proceedings of 16th International Conference on Distributed Computing Systems","volume":"539 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133978087","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 : 1996-05-27DOI: 10.1109/ICDCS.1996.507998
T. Wilkinson, Kevin Murray
In this paper we present an evaluation of Angel, a single address space operating system, originally designed in 1992, which has been developed over the past few years. The purpose of this work was to examine how we could simplify the kernel and service structure using the single address space as the enabling technology. We believe that in so doing, we could achieve far better performance and simpler extensibility compared to other micro-kernel architectures. We recently completed a prototype system based around the PC/486 architecture which has allowed us to evaluate our claims and postulations. An initial analysis of this prototype has been performed to examine the system's structure and performance characteristics. This demonstrates an architecture which is more flexible, faster and smaller than monolithic operating systems.
{"title":"Evaluation of a distributed single address space operating system","authors":"T. Wilkinson, Kevin Murray","doi":"10.1109/ICDCS.1996.507998","DOIUrl":"https://doi.org/10.1109/ICDCS.1996.507998","url":null,"abstract":"In this paper we present an evaluation of Angel, a single address space operating system, originally designed in 1992, which has been developed over the past few years. The purpose of this work was to examine how we could simplify the kernel and service structure using the single address space as the enabling technology. We believe that in so doing, we could achieve far better performance and simpler extensibility compared to other micro-kernel architectures. We recently completed a prototype system based around the PC/486 architecture which has allowed us to evaluate our claims and postulations. An initial analysis of this prototype has been performed to examine the system's structure and performance characteristics. This demonstrates an architecture which is more flexible, faster and smaller than monolithic operating systems.","PeriodicalId":159322,"journal":{"name":"Proceedings of 16th International Conference on Distributed Computing Systems","volume":"313 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134410717","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}