Pub Date : 2002-07-02DOI: 10.1109/ICDCS.2002.1022257
Alain Cournier, A. Datta, F. Petit, V. Villain
We present the first snap-stabilizing propagation of information with feedback (PIF) protocol in arbitrary networks. A snap-stabilizing protocol, starting from any arbitrary initial system configuration, always behaves according to its specification. Our protocol is distributed, deterministic, and does not use a pre-constructed spanning tree.
{"title":"Snap-stabilizing PIF algorithm in arbitrary networks","authors":"Alain Cournier, A. Datta, F. Petit, V. Villain","doi":"10.1109/ICDCS.2002.1022257","DOIUrl":"https://doi.org/10.1109/ICDCS.2002.1022257","url":null,"abstract":"We present the first snap-stabilizing propagation of information with feedback (PIF) protocol in arbitrary networks. A snap-stabilizing protocol, starting from any arbitrary initial system configuration, always behaves according to its specification. Our protocol is distributed, deterministic, and does not use a pre-constructed spanning tree.","PeriodicalId":186210,"journal":{"name":"Proceedings 22nd International Conference on Distributed Computing Systems","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125396286","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 : 2002-07-02DOI: 10.1109/ICDCS.2002.1022283
Stefan Pleisch, A. Schiper
Mobile agents are computer programs that act autonomously on behalf of a user and travel through a network of heterogeneous machines. To enable mobile agent technology for e-business, transaction support needs to be provided, in particular execution atomicity. Execution atomicity ensures that either all operations of the agent succeed, or none at all, and needs to be ensured also in the face of infrastructure failures. We distinguish between blocking and non-blocking solutions for transactional mobile agents, i.e., mobile agents, that execute as a transaction. The approach presented in the paper is non-blocking. A non-blocking transactional mobile agent execution has the important advantage, that it can make progress despite failures.
{"title":"Non-blocking transactional mobile agent execution","authors":"Stefan Pleisch, A. Schiper","doi":"10.1109/ICDCS.2002.1022283","DOIUrl":"https://doi.org/10.1109/ICDCS.2002.1022283","url":null,"abstract":"Mobile agents are computer programs that act autonomously on behalf of a user and travel through a network of heterogeneous machines. To enable mobile agent technology for e-business, transaction support needs to be provided, in particular execution atomicity. Execution atomicity ensures that either all operations of the agent succeed, or none at all, and needs to be ensured also in the face of infrastructure failures. We distinguish between blocking and non-blocking solutions for transactional mobile agents, i.e., mobile agents, that execute as a transaction. The approach presented in the paper is non-blocking. A non-blocking transactional mobile agent execution has the important advantage, that it can make progress despite failures.","PeriodicalId":186210,"journal":{"name":"Proceedings 22nd International Conference on Distributed Computing Systems","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115819054","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 : 2002-07-02DOI: 10.1109/ICDCS.2002.1022289
C. Intanagonwiwat, D. Estrin, R. Govindan, J. Heidemann
In-network data aggregation is essential for wireless sensor networks where energy resources are limited. In a previously proposed data dissemination scheme (directed diffusion with opportunistic aggregation), data is opportunistically aggregated at intermediate nodes on a low-latency tree. In this paper, we explore and evaluate greedy aggregation, a novel approach that adjusts aggregation points to increase the amount of path sharing, reducing energy consumption. Our preliminary results suggest that, under investigated scenarios, greedy aggregation can achieve up to 45% energy savings over opportunistic aggregation in high-density networks without adversely impacting latency or robustness.
{"title":"Impact of network density on data aggregation in wireless sensor networks","authors":"C. Intanagonwiwat, D. Estrin, R. Govindan, J. Heidemann","doi":"10.1109/ICDCS.2002.1022289","DOIUrl":"https://doi.org/10.1109/ICDCS.2002.1022289","url":null,"abstract":"In-network data aggregation is essential for wireless sensor networks where energy resources are limited. In a previously proposed data dissemination scheme (directed diffusion with opportunistic aggregation), data is opportunistically aggregated at intermediate nodes on a low-latency tree. In this paper, we explore and evaluate greedy aggregation, a novel approach that adjusts aggregation points to increase the amount of path sharing, reducing energy consumption. Our preliminary results suggest that, under investigated scenarios, greedy aggregation can achieve up to 45% energy savings over opportunistic aggregation in high-density networks without adversely impacting latency or robustness.","PeriodicalId":186210,"journal":{"name":"Proceedings 22nd International Conference on Distributed Computing Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129147848","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 : 2002-07-02DOI: 10.1109/ICDCS.2002.1022255
Daisuke Kondou, Hideo Masuda, T. Masuzawa
Self-stabilization is a promising paradigm for achieving fault-tolerance of distributed systems. A self-stabilizing protocol can converge to its intended behavior even when it starts from any system configuration, and, thus, can tolerate any type and any number of transient faults. The PIF (propagation of information with feedback) scheme in a tree network allows the root process to broadcast its information to all other processes and to collect their responses. Many distributed systems utilize the PIF scheme as a fundamental communication scheme. This paper first formalizes the pipelined PIF in tree networks, and proposes a self-stabilizing protocol for the pipelined PIF. The protocol applies the PIF to a sequence of information in a pipelined fashion. The protocol has stabilizing time of O(h) (where h is the height of the tree network). After stabilization, it completes each PIF in O(h) asynchronous rounds and has throughput of O(1). Moreover, the protocol achieves fault-containment: for a complete binary tree network, its expected stabilizing time from 1-faulty configurations is O(1).
{"title":"A self-stabilizing protocol for pipelined PIF in tree networks","authors":"Daisuke Kondou, Hideo Masuda, T. Masuzawa","doi":"10.1109/ICDCS.2002.1022255","DOIUrl":"https://doi.org/10.1109/ICDCS.2002.1022255","url":null,"abstract":"Self-stabilization is a promising paradigm for achieving fault-tolerance of distributed systems. A self-stabilizing protocol can converge to its intended behavior even when it starts from any system configuration, and, thus, can tolerate any type and any number of transient faults. The PIF (propagation of information with feedback) scheme in a tree network allows the root process to broadcast its information to all other processes and to collect their responses. Many distributed systems utilize the PIF scheme as a fundamental communication scheme. This paper first formalizes the pipelined PIF in tree networks, and proposes a self-stabilizing protocol for the pipelined PIF. The protocol applies the PIF to a sequence of information in a pipelined fashion. The protocol has stabilizing time of O(h) (where h is the height of the tree network). After stabilization, it completes each PIF in O(h) asynchronous rounds and has throughput of O(1). Moreover, the protocol achieves fault-containment: for a complete binary tree network, its expected stabilizing time from 1-faulty configurations is O(1).","PeriodicalId":186210,"journal":{"name":"Proceedings 22nd International Conference on Distributed Computing Systems","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113980842","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 : 2002-07-02DOI: 10.1109/ICDCS.2002.1022261
Tsutomu Gamou
The on-demand downloading of application code over a wireless network is an emerging paradigm for the distributed environment of mobile computing devices. In this environment, a user must wait while a mobile computing device fetches the application code over the network prior to execution. To reduce this downloading latency, we have developed a download approach based on working sets, and have designed and implemented a working-set generator that defines working sets by focusing on the intervals during which a program refers to junctions, variables, and constants. The program invocation times with this approach, simulated using trace information obtained from actual program behavior on Linux, have been compared with those of all-at-once, page, class, and symbol download approaches. This simulation showed that the working-set approach can reduce the download-execution time compared to that with the four other approaches.
{"title":"A working-set approach to reduce the download-execution time of mobile programs","authors":"Tsutomu Gamou","doi":"10.1109/ICDCS.2002.1022261","DOIUrl":"https://doi.org/10.1109/ICDCS.2002.1022261","url":null,"abstract":"The on-demand downloading of application code over a wireless network is an emerging paradigm for the distributed environment of mobile computing devices. In this environment, a user must wait while a mobile computing device fetches the application code over the network prior to execution. To reduce this downloading latency, we have developed a download approach based on working sets, and have designed and implemented a working-set generator that defines working sets by focusing on the intervals during which a program refers to junctions, variables, and constants. The program invocation times with this approach, simulated using trace information obtained from actual program behavior on Linux, have been compared with those of all-at-once, page, class, and symbol download approaches. This simulation showed that the working-set approach can reduce the download-execution time compared to that with the four other approaches.","PeriodicalId":186210,"journal":{"name":"Proceedings 22nd International Conference on Distributed Computing Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130706946","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 : 2002-07-02DOI: 10.1109/ICDCS.2002.1022288
Guanling Lee, Yi-Ning Pan, Arbee L. P. Chen
The problem of transmitting data items with timing constraint in the multiple broadcast channels where clients equipped with multiple receivers is studied. In our approach, the data items are divided into two sets, the broadcast data set and the on-demand data set. The data items in the broadcast data set is periodically broadcast on the broadcast channels while the data items in the on-demand data set are transmitted when they are requested. The server offline allocates the data items in the broadcast data set to the multiple broadcast channels. The clients retrieved data items from the broadcast channels are guaranteed to receive them within the timing constraint. Once the desired data item is not included in the broadcast channels, clients make requests associated with deadlines to the server. By using the bandwidth remaining for the on-demand mode, the server broadcasts the requested data items in an online fashion. The intention of our work is to serve as many requests as possible.
{"title":"Scheduling real-time data items in multiple channels and multiple receivers environments","authors":"Guanling Lee, Yi-Ning Pan, Arbee L. P. Chen","doi":"10.1109/ICDCS.2002.1022288","DOIUrl":"https://doi.org/10.1109/ICDCS.2002.1022288","url":null,"abstract":"The problem of transmitting data items with timing constraint in the multiple broadcast channels where clients equipped with multiple receivers is studied. In our approach, the data items are divided into two sets, the broadcast data set and the on-demand data set. The data items in the broadcast data set is periodically broadcast on the broadcast channels while the data items in the on-demand data set are transmitted when they are requested. The server offline allocates the data items in the broadcast data set to the multiple broadcast channels. The clients retrieved data items from the broadcast channels are guaranteed to receive them within the timing constraint. Once the desired data item is not included in the broadcast channels, clients make requests associated with deadlines to the server. By using the bandwidth remaining for the on-demand mode, the server broadcasts the requested data items in an online fashion. The intention of our work is to serve as many requests as possible.","PeriodicalId":186210,"journal":{"name":"Proceedings 22nd International Conference on Distributed Computing Systems","volume":"211 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134467402","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 : 2002-07-02DOI: 10.1109/ICDCS.2002.1022254
Yang Wang, Xiangyang Li
We propose a new geometric spanner, for wireless ad hoc networks, which can be constructed efficiently in a distributed manner. It combines the connected dominating set and the local Delaunay graph to form the backbone of a wireless network. This new spanner has the following attractive properties: (1) the backbone is a planar graph; (2) the node degree of the backbone is bounded from above by a positive constant; (3) it is a spanner both for hops and length; moreover, we show that, given any two nodes u and /spl upsi/, there is a path connecting them in the backbone such that its length is no more than 6 times that of the shortest path and the number of links is no more than 3 times that of the shortest path; (4) it can be constructed locally and is easy to maintain when the nodes move around; and (5) we show that the computation cost of each node is at most O(d log d), where d is its l-hop neighbors in the original unit disk graph, and the communication cost of each node is bounded by a constant. Simulation results are also presented for studying its practical performance.
{"title":"Geometric spanners for wireless ad hoc networks","authors":"Yang Wang, Xiangyang Li","doi":"10.1109/ICDCS.2002.1022254","DOIUrl":"https://doi.org/10.1109/ICDCS.2002.1022254","url":null,"abstract":"We propose a new geometric spanner, for wireless ad hoc networks, which can be constructed efficiently in a distributed manner. It combines the connected dominating set and the local Delaunay graph to form the backbone of a wireless network. This new spanner has the following attractive properties: (1) the backbone is a planar graph; (2) the node degree of the backbone is bounded from above by a positive constant; (3) it is a spanner both for hops and length; moreover, we show that, given any two nodes u and /spl upsi/, there is a path connecting them in the backbone such that its length is no more than 6 times that of the shortest path and the number of links is no more than 3 times that of the shortest path; (4) it can be constructed locally and is easy to maintain when the nodes move around; and (5) we show that the computation cost of each node is at most O(d log d), where d is its l-hop neighbors in the original unit disk graph, and the communication cost of each node is bounded by a constant. Simulation results are also presented for studying its practical performance.","PeriodicalId":186210,"journal":{"name":"Proceedings 22nd International Conference on Distributed Computing Systems","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132237822","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 : 2002-07-02DOI: 10.1109/ICDCS.2002.1022295
Jiannong Cao, Xinyu Feng, Jian Lu, Sajal K. Das
This paper presents a mailbox-based scheme for designing flexible and adaptive message delivery protocols in mobile agent (MA) systems. The scheme associates each mobile agent with a mailbox while allowing the decoupling between them, i.e., a mobile agent can migrate to a new site without bringing its mailbox. By separating the concerns of locating the mailbox of a mobile agent and delivering a message to the agent, we obtain a large space of protocol design with flexibility. Using a three-dimensional model based on the scheme, we have developed a taxonomy of MA communication protocols, which not only covers, as special cases, several known MA message delivery protocols, but also allows for the design of new ones well suited for various application requirements. We describe such an efficient and adaptive protocol derived front the model. The protocol guarantees reliable delivery of messages to mobile agents. We analyze the design trade-offs and performance of the protocol, using an analytic model as well as extensive simulation experiments.
{"title":"Design of adaptive and reliable mobile agent communication protocols","authors":"Jiannong Cao, Xinyu Feng, Jian Lu, Sajal K. Das","doi":"10.1109/ICDCS.2002.1022295","DOIUrl":"https://doi.org/10.1109/ICDCS.2002.1022295","url":null,"abstract":"This paper presents a mailbox-based scheme for designing flexible and adaptive message delivery protocols in mobile agent (MA) systems. The scheme associates each mobile agent with a mailbox while allowing the decoupling between them, i.e., a mobile agent can migrate to a new site without bringing its mailbox. By separating the concerns of locating the mailbox of a mobile agent and delivering a message to the agent, we obtain a large space of protocol design with flexibility. Using a three-dimensional model based on the scheme, we have developed a taxonomy of MA communication protocols, which not only covers, as special cases, several known MA message delivery protocols, but also allows for the design of new ones well suited for various application requirements. We describe such an efficient and adaptive protocol derived front the model. The protocol guarantees reliable delivery of messages to mobile agents. We analyze the design trade-offs and performance of the protocol, using an analytic model as well as extensive simulation experiments.","PeriodicalId":186210,"journal":{"name":"Proceedings 22nd International Conference on Distributed Computing Systems","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129552910","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 : 2002-07-02DOI: 10.1109/ICDCS.2002.1022270
W. Steiner, M. Paulitsch
Immediately after power-up, synchronous distributed systems need some time until essential timing properties, which are required to operate correctly, are established. We say that synchronous systems are initially in asynchronous operation. In this paper, we present an algorithm and architectural guidelines that assure the transition from asynchronous to synchronous operation within a bounded duration even in case of failures.
{"title":"The transition from asynchronous to synchronous system operation: an approach for distributed fault-tolerant systems","authors":"W. Steiner, M. Paulitsch","doi":"10.1109/ICDCS.2002.1022270","DOIUrl":"https://doi.org/10.1109/ICDCS.2002.1022270","url":null,"abstract":"Immediately after power-up, synchronous distributed systems need some time until essential timing properties, which are required to operate correctly, are established. We say that synchronous systems are initially in asynchronous operation. In this paper, we present an algorithm and architectural guidelines that assure the transition from asynchronous to synchronous operation within a bounded duration even in case of failures.","PeriodicalId":186210,"journal":{"name":"Proceedings 22nd International Conference on Distributed Computing Systems","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131339564","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 : 2002-07-02DOI: 10.1109/ICDCS.2002.1022312
John R. Douceur, A. Adya, W. Bolosky, D. Simon, M. Theimer
The Farsite distributed file system provides availability by replicating each file onto multiple desktop computers. Since this replication consumes significant storage space, it is important to reclaim used space where possible. Measurement of over 500 desktop file systems shows that nearly half of all consumed space is occupied by duplicate files. We present a mechanism to reclaim space from this incidental duplication to make it available for controlled file replication. Our mechanism includes: (1) convergent encryption, which enables duplicate files to be coalesced into the space of a single file, even if the files are encrypted with different users' keys; and (2) SALAD, a Self-Arranging Lossy Associative Database for aggregating file content and location information in a decentralized, scalable, fault-tolerant manner. Large-scale simulation experiments show that the duplicate-file coalescing system is scalable, highly effective, and fault-tolerant.
{"title":"Reclaiming space from duplicate files in a serverless distributed file system","authors":"John R. Douceur, A. Adya, W. Bolosky, D. Simon, M. Theimer","doi":"10.1109/ICDCS.2002.1022312","DOIUrl":"https://doi.org/10.1109/ICDCS.2002.1022312","url":null,"abstract":"The Farsite distributed file system provides availability by replicating each file onto multiple desktop computers. Since this replication consumes significant storage space, it is important to reclaim used space where possible. Measurement of over 500 desktop file systems shows that nearly half of all consumed space is occupied by duplicate files. We present a mechanism to reclaim space from this incidental duplication to make it available for controlled file replication. Our mechanism includes: (1) convergent encryption, which enables duplicate files to be coalesced into the space of a single file, even if the files are encrypted with different users' keys; and (2) SALAD, a Self-Arranging Lossy Associative Database for aggregating file content and location information in a decentralized, scalable, fault-tolerant manner. Large-scale simulation experiments show that the duplicate-file coalescing system is scalable, highly effective, and fault-tolerant.","PeriodicalId":186210,"journal":{"name":"Proceedings 22nd International Conference on Distributed Computing Systems","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133327403","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}