Providing a seamless handoff and quality of service (QoS) guarantees is one of the key issues in real-time services. Several IPv6 mobility management schemes have been proposed and can provide uninterrupted service. However, these schemes either have synchronization issues or introduce signaling overhead and high packet loss rate. This paper presents a scheme that reduces the handoff latency based on the location and movement pattern of a Mobile Node (MN). An MN can detect its movement actively and forecast the handoff, which alleviates the communication cost between the MN and its Access Router (AR). Furthermore, by setting the dynamic interval in an appropriate range, the MN’s burden can also be alleviated. Finally, by performance evaluation using both theoretical analysis and computer simulations, we show that the proposed scheme can lower the handoff latency efficiently.
{"title":"A Low Latency Handoff Scheme Based on the Location and Movement Pattern","authors":"Fei Shi, Keqiu Li, Yanming Shen","doi":"10.1109/ISPA.2009.11","DOIUrl":"https://doi.org/10.1109/ISPA.2009.11","url":null,"abstract":"Providing a seamless handoff and quality of service (QoS) guarantees is one of the key issues in real-time services. Several IPv6 mobility management schemes have been proposed and can provide uninterrupted service. However, these schemes either have synchronization issues or introduce signaling overhead and high packet loss rate. This paper presents a scheme that reduces the handoff latency based on the location and movement pattern of a Mobile Node (MN). An MN can detect its movement actively and forecast the handoff, which alleviates the communication cost between the MN and its Access Router (AR). Furthermore, by setting the dynamic interval in an appropriate range, the MN’s burden can also be alleviated. Finally, by performance evaluation using both theoretical analysis and computer simulations, we show that the proposed scheme can lower the handoff latency efficiently.","PeriodicalId":346815,"journal":{"name":"2009 IEEE International Symposium on Parallel and Distributed Processing with Applications","volume":"226 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116113496","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}
Jeremy Espenshade, Andrew Pangborn, G. Laszewski, Douglas Roberts, J. Cavenaugh
Like many modern techniques for scientific analysis, flow cytometry produces massive amounts of data that must be analyzed and clustered intelligently to be useful. Current manual binning techniques are cumbersome and limited in both the quality and quantity of analysis produced. To address the quality of results, a new framework applying two different sets of clustering algorithms and inference methods are implemented. The two methods investigated are fuzzy c-means with minimum description length inference and k-medoids with BIC. These approaches lend themselves to large scale parallel processing. To address the computational demands, the Nvidia CUDA framework and Tesla architecture are utilized. The resulting performance demonstrated 1-2 orders of magnitude improvement over an equivalent sequential version. The quality of results is promising and motivates further research and development in this direction.
{"title":"Accelerating Partitional Algorithms for Flow Cytometry on GPUs","authors":"Jeremy Espenshade, Andrew Pangborn, G. Laszewski, Douglas Roberts, J. Cavenaugh","doi":"10.1109/ISPA.2009.29","DOIUrl":"https://doi.org/10.1109/ISPA.2009.29","url":null,"abstract":"Like many modern techniques for scientific analysis, flow cytometry produces massive amounts of data that must be analyzed and clustered intelligently to be useful. Current manual binning techniques are cumbersome and limited in both the quality and quantity of analysis produced. To address the quality of results, a new framework applying two different sets of clustering algorithms and inference methods are implemented. The two methods investigated are fuzzy c-means with minimum description length inference and k-medoids with BIC. These approaches lend themselves to large scale parallel processing. To address the computational demands, the Nvidia CUDA framework and Tesla architecture are utilized. The resulting performance demonstrated 1-2 orders of magnitude improvement over an equivalent sequential version. The quality of results is promising and motivates further research and development in this direction.","PeriodicalId":346815,"journal":{"name":"2009 IEEE International Symposium on Parallel and Distributed Processing with Applications","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123982920","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}
Grid computing technology makes it possibly to use scientific workflow to be shared and reused among different users. However, a scientific workflow model usually needs to be tailored during reuse because of different problem contexts met by different users. These change logs provide additional information to help users customize scientific workflow. In this paper, we present a change sequence mining approach to automatically induce customized workflow based on different scientific experiment contexts. A docking case for drug design is described to validate the approach.
{"title":"Change Sequence Mining in Context-Aware Scientific Workflow","authors":"Yi Wang, Jian Cao, Minglu Li","doi":"10.1109/ISPA.2009.26","DOIUrl":"https://doi.org/10.1109/ISPA.2009.26","url":null,"abstract":"Grid computing technology makes it possibly to use scientific workflow to be shared and reused among different users. However, a scientific workflow model usually needs to be tailored during reuse because of different problem contexts met by different users. These change logs provide additional information to help users customize scientific workflow. In this paper, we present a change sequence mining approach to automatically induce customized workflow based on different scientific experiment contexts. A docking case for drug design is described to validate the approach.","PeriodicalId":346815,"journal":{"name":"2009 IEEE International Symposium on Parallel and Distributed Processing with Applications","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124033610","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}
This paper first discusses the classic methods of covert communication to traverse the firewall devices which control the network communication. And based on the analysis of IPSec protocol architecture, that the worse of network compatibility of IPSec is got. So the new IPSec over HTTP protocol based on IPSec tunnel and HTTP tunnel is exposed including its structure and procedure. The soft structure of FreeSWAN is improved and the performance test data are presented in order to validate this new protocol. Finally, the performance of the new system is analyzed detailedly
本文首先讨论了隐蔽通信的经典方法，即穿越控制网络通信的防火墙设备。在对IPSec协议体系结构进行分析的基础上，得出了IPSec网络兼容性的缺点。在此基础上，提出了一种基于IPSec隧道和HTTP隧道的新型IPSec over HTTP协议，包括其结构和实现过程。为了验证新协议的有效性，对FreeSWAN的软结构进行了改进，并给出了性能测试数据。最后，对新系统的性能进行了详细分析
{"title":"One New Research about IPSec Communication Based on HTTP Tunnel","authors":"Mei Song, Yun-he Zhang","doi":"10.1109/ISPA.2009.44","DOIUrl":"https://doi.org/10.1109/ISPA.2009.44","url":null,"abstract":"This paper first discusses the classic methods of covert communication to traverse the firewall devices which control the network communication. And based on the analysis of IPSec protocol architecture, that the worse of network compatibility of IPSec is got. So the new IPSec over HTTP protocol based on IPSec tunnel and HTTP tunnel is exposed including its structure and procedure. The soft structure of FreeSWAN is improved and the performance test data are presented in order to validate this new protocol. Finally, the performance of the new system is analyzed detailedly","PeriodicalId":346815,"journal":{"name":"2009 IEEE International Symposium on Parallel and Distributed Processing with Applications","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122156712","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}
Wireless sensor and actor networks (WSANs) have attracted much attention in the recent years. In WSANs, sensor nodes are in charge of the sensing task, while the actor nodes take actions in response to the sensed phenomena or the detected event. In order to execute the correct operations, the applications typically have to process the data or messages from the different sensors in the same order. This paper presents a Consistent Message Ordering (CMO) algorithm, which ensures that messages from the different sensors arrive at the different actors in a consistent order. The significance of the algorithm is fully localized, asynchronous and energy-efficient. We prove the correctness of the algorithm, and analyze the theoretical message complexity. And the experimental results show that CMO algorithm improves the performance at least 60% over TMOS algorithm in many situations.
{"title":"Consistent Message Ordering in Wireless Sensor and Actor Networks","authors":"Yang Wang, Liusheng Huang, Hongli Xu, G. Wang","doi":"10.1109/ISPA.2009.67","DOIUrl":"https://doi.org/10.1109/ISPA.2009.67","url":null,"abstract":"Wireless sensor and actor networks (WSANs) have attracted much attention in the recent years. In WSANs, sensor nodes are in charge of the sensing task, while the actor nodes take actions in response to the sensed phenomena or the detected event. In order to execute the correct operations, the applications typically have to process the data or messages from the different sensors in the same order. This paper presents a Consistent Message Ordering (CMO) algorithm, which ensures that messages from the different sensors arrive at the different actors in a consistent order. The significance of the algorithm is fully localized, asynchronous and energy-efficient. We prove the correctness of the algorithm, and analyze the theoretical message complexity. And the experimental results show that CMO algorithm improves the performance at least 60% over TMOS algorithm in many situations.","PeriodicalId":346815,"journal":{"name":"2009 IEEE International Symposium on Parallel and Distributed Processing with Applications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130183212","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}
Most traditional Distributed Shared Memory (DSM) systems support data sharing in multi-process applications. This paper proposed a Multi-threaded Multi-home DSM system (MM-DSM) to support both data sharing and computation synchronization in multi-threaded applications whose threads are grouped into bundles and distributed across multiple computers for parallel execution. Globally shared data are rearranged and assigned to different thread bundles based on their access patterns. As thread bundles move around, their hosting nodes will act as the homes of the associated data blocks to reduce communication cost. Programmers can still stick to the shared memory programming paradigm whereas data consistency, distributed lock, false sharing and multiple writes are taken care of by MM-DSM. Experimental results demonstrate its effectiveness and correctness.
{"title":"MM-DSM: Multi-threaded Multi-home Distributed Shared Memory Systems","authors":"C. Mei, Hai Jiang, J. Jenness","doi":"10.1109/ISPA.2009.69","DOIUrl":"https://doi.org/10.1109/ISPA.2009.69","url":null,"abstract":"Most traditional Distributed Shared Memory (DSM) systems support data sharing in multi-process applications. This paper proposed a Multi-threaded Multi-home DSM system (MM-DSM) to support both data sharing and computation synchronization in multi-threaded applications whose threads are grouped into bundles and distributed across multiple computers for parallel execution. Globally shared data are rearranged and assigned to different thread bundles based on their access patterns. As thread bundles move around, their hosting nodes will act as the homes of the associated data blocks to reduce communication cost. Programmers can still stick to the shared memory programming paradigm whereas data consistency, distributed lock, false sharing and multiple writes are taken care of by MM-DSM. Experimental results demonstrate its effectiveness and correctness.","PeriodicalId":346815,"journal":{"name":"2009 IEEE International Symposium on Parallel and Distributed Processing with Applications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129196667","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}
Botnets with the centralized architecture provide a simple, low-latency, anonymous and efficient real-time communication platform for the botnet controllers. To our knowledge, most of the latest detected large-scale botnets are based on the centralized structure with HTTP or customized protocols. Therefore, centralized botnets detection helps greatly improve control of unwanted traffic. The main contribution of this study is the development of a common detection mechanism aiming at the centralized botnets. In this work we investigate the intrinsic characteristics based on the distributed yet bursting property of the centralized botnets. Our study shows that there exist great similarity and synchronization among the behaviors and the command and control (C&C) traffic of the bots, because the bots are controlled to operate according to the programmed schedule. Firstly we can determine if the groups of flows are suspectable by performing evaluation on the payload similarity and sequence correlation. Further, we will monitor and keep tracking with the collective and simultaneous behaviors of the suspicious groups of hosts. As is shown by conducting experiments, the proposed method can detect and hold back the centralized botnets effectively before they seriously influence the normal operation on the wide-scale network.
{"title":"Centralized Botnet Detection by Traffic Aggregation","authors":"Tao Wang, Shunzheng Yu","doi":"10.1109/ISPA.2009.74","DOIUrl":"https://doi.org/10.1109/ISPA.2009.74","url":null,"abstract":"Botnets with the centralized architecture provide a simple, low-latency, anonymous and efficient real-time communication platform for the botnet controllers. To our knowledge, most of the latest detected large-scale botnets are based on the centralized structure with HTTP or customized protocols. Therefore, centralized botnets detection helps greatly improve control of unwanted traffic. The main contribution of this study is the development of a common detection mechanism aiming at the centralized botnets. In this work we investigate the intrinsic characteristics based on the distributed yet bursting property of the centralized botnets. Our study shows that there exist great similarity and synchronization among the behaviors and the command and control (C&C) traffic of the bots, because the bots are controlled to operate according to the programmed schedule. Firstly we can determine if the groups of flows are suspectable by performing evaluation on the payload similarity and sequence correlation. Further, we will monitor and keep tracking with the collective and simultaneous behaviors of the suspicious groups of hosts. As is shown by conducting experiments, the proposed method can detect and hold back the centralized botnets effectively before they seriously influence the normal operation on the wide-scale network.","PeriodicalId":346815,"journal":{"name":"2009 IEEE International Symposium on Parallel and Distributed Processing with Applications","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128170463","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}
This paper introduces a constraint processing language called: SimSync to facilitate synchronization control in concurrent systems modeling. We define the primitive elements of the language to specify both qualitative and quantitative constraints in synchronization control. A table template is designed to organize those elements as a user-friendly definition interface. We also construct a language parser to generate agent instances which execute a parallelizable pattern matching algorithm to determine satisfiability of synchronization constraints in runtimes of concurrent systems. By applying the concept of staged event-driven architecture (SEDA), we make the implementation of the constraint processing scalable by designing the algorithm into a data-driven and distributed fashion. In this paper a SimSync module incorporated into a variance of Petri-net, Object-Process Network (OPN) is provided. An application of large-scale transportation management problem is also shown as a concrete example to illustrate the extensibility of SimSync.
{"title":"SimSync: A Table-Based Constraint Processing Language For Synchronization Control","authors":"Ke Huang, Zhihong Li, Benjamin H. Y. Koo, T. Wang","doi":"10.1109/ISPA.2009.86","DOIUrl":"https://doi.org/10.1109/ISPA.2009.86","url":null,"abstract":"This paper introduces a constraint processing language called: SimSync to facilitate synchronization control in concurrent systems modeling. We define the primitive elements of the language to specify both qualitative and quantitative constraints in synchronization control. A table template is designed to organize those elements as a user-friendly definition interface. We also construct a language parser to generate agent instances which execute a parallelizable pattern matching algorithm to determine satisfiability of synchronization constraints in runtimes of concurrent systems. By applying the concept of staged event-driven architecture (SEDA), we make the implementation of the constraint processing scalable by designing the algorithm into a data-driven and distributed fashion. In this paper a SimSync module incorporated into a variance of Petri-net, Object-Process Network (OPN) is provided. An application of large-scale transportation management problem is also shown as a concrete example to illustrate the extensibility of SimSync.","PeriodicalId":346815,"journal":{"name":"2009 IEEE International Symposium on Parallel and Distributed Processing with Applications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126932195","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 virtual machine (VM) systems, with the increase in the number of VMs and the demands of applications, the main memory is becoming a bottleneck of application performance. To improve paging performance for memory-intensive or I/O-intensive workloads, we propose the hypervisor REMOte disk CAche (REMOCA), which allows a virtual machine to use the memory resources on other physical machines as its cache between its virtual memory and virtual disk devices. The goal of REMOCA is to reduce disk accesses, which is much slower than transferring memory pages over modern interconnect networks. As a result, the average disk I/O latency can be improved. REMOCA is implemented within the hypervisor, by intercepting guest events such as page evictions and disk accesses. This design is transparent to the applications, and is compatible with existing techniques like ballooning and ghost buffer. Moreover, a combination of them can provide a more flexible resource management policy. Our experimental results show that REMOCA can efficiently alleviate the impact of thrashing behavior, and also significantly improve the performance for real-world I/O intensive applications.
{"title":"REMOCA: Hypervisor Remote Disk Cache","authors":"Haogang Chen, Xiaolin Wang, Zhenlin Wang, Xiang Wen, Xinxin Jin, Yingwei Luo, Xiaoming Li","doi":"10.1109/ISPA.2009.27","DOIUrl":"https://doi.org/10.1109/ISPA.2009.27","url":null,"abstract":"In virtual machine (VM) systems, with the increase in the number of VMs and the demands of applications, the main memory is becoming a bottleneck of application performance. To improve paging performance for memory-intensive or I/O-intensive workloads, we propose the hypervisor REMOte disk CAche (REMOCA), which allows a virtual machine to use the memory resources on other physical machines as its cache between its virtual memory and virtual disk devices. The goal of REMOCA is to reduce disk accesses, which is much slower than transferring memory pages over modern interconnect networks. As a result, the average disk I/O latency can be improved. REMOCA is implemented within the hypervisor, by intercepting guest events such as page evictions and disk accesses. This design is transparent to the applications, and is compatible with existing techniques like ballooning and ghost buffer. Moreover, a combination of them can provide a more flexible resource management policy. Our experimental results show that REMOCA can efficiently alleviate the impact of thrashing behavior, and also significantly improve the performance for real-world I/O intensive applications.","PeriodicalId":346815,"journal":{"name":"2009 IEEE International Symposium on Parallel and Distributed Processing with Applications","volume":"270 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134190389","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}
Jie Cheng, Xiaoguang Lin, Yuanchun Zhou, Jianhui Li
Distributed atmospheric data are often stored and managed in diverse regional and global repositories. The scientific process requires composition of these resources to solve a specific atmospheric science problem. A challenge is how to harvest data and models for designing and executing experiments in a seamless manner. Moreover, data-intensive scientific experiments with large-scale scientific data processing are iterative, dynamic and human centered. In particular, the atmospheric scientific experiments usually include some fixed steps, such as data discovery, access, preprocessing, transformation, visualization. A web service-enabled workflow system is a flexible tool for accessing distributed scientific data, and executing complex analysis on it. In this paper, we describe a four-layered architecture of the workflow system, which consists of web interaction layer, workflow engine layer, workflow components layer and resource layer. We also develop an intuitive and easy-to-use web based toolkit and apply it to atmospheric data processing.
{"title":"A Web Based Workflow System for Distributed Atmospheric Data Processing","authors":"Jie Cheng, Xiaoguang Lin, Yuanchun Zhou, Jianhui Li","doi":"10.1109/ISPA.2009.30","DOIUrl":"https://doi.org/10.1109/ISPA.2009.30","url":null,"abstract":"Distributed atmospheric data are often stored and managed in diverse regional and global repositories. The scientific process requires composition of these resources to solve a specific atmospheric science problem. A challenge is how to harvest data and models for designing and executing experiments in a seamless manner. Moreover, data-intensive scientific experiments with large-scale scientific data processing are iterative, dynamic and human centered. In particular, the atmospheric scientific experiments usually include some fixed steps, such as data discovery, access, preprocessing, transformation, visualization. A web service-enabled workflow system is a flexible tool for accessing distributed scientific data, and executing complex analysis on it. In this paper, we describe a four-layered architecture of the workflow system, which consists of web interaction layer, workflow engine layer, workflow components layer and resource layer. We also develop an intuitive and easy-to-use web based toolkit and apply it to atmospheric data processing.","PeriodicalId":346815,"journal":{"name":"2009 IEEE International Symposium on Parallel and Distributed Processing with Applications","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121206175","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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