Pub Date : 2003-10-27DOI: 10.1109/MASCOT.2003.1240636
M. Calzarossa
The fast technological evolution and the convergence of fixed and mobile communication infrastructures have led to the realization of a large variety of innovative applications and services that have become an integral part of our society. Efficiency, reliability, availability and security, i.e., quality of service, are fundamental requirements for these applications. In this framework, performance evaluation and capacity planning play a key role. This paper presents an ongoing research project carried out under the FIRB Programme of the Italian Ministry of Education, Universities and Research. The project addresses basic and foundational research in performance evaluation with the objective of developing new techniques, methodologies and tools for the analysis of the complex systems and applications that drive our society.
{"title":"Perf: an ongoing research project on performance evaluation","authors":"M. Calzarossa","doi":"10.1109/MASCOT.2003.1240636","DOIUrl":"https://doi.org/10.1109/MASCOT.2003.1240636","url":null,"abstract":"The fast technological evolution and the convergence of fixed and mobile communication infrastructures have led to the realization of a large variety of innovative applications and services that have become an integral part of our society. Efficiency, reliability, availability and security, i.e., quality of service, are fundamental requirements for these applications. In this framework, performance evaluation and capacity planning play a key role. This paper presents an ongoing research project carried out under the FIRB Programme of the Italian Ministry of Education, Universities and Research. The project addresses basic and foundational research in performance evaluation with the objective of developing new techniques, methodologies and tools for the analysis of the complex systems and applications that drive our society.","PeriodicalId":344411,"journal":{"name":"11th IEEE/ACM International Symposium on Modeling, Analysis and Simulation of Computer Telecommunications Systems, 2003. MASCOTS 2003.","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126599208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-27DOI: 10.1109/MASCOT.2003.1240666
K. Yocum, Ethan Eade, Julius Degesys, David Becker, J. Chase, Amin Vahdat
Scalability is the primary challenge to studying large complex network systems with network emulation. This paper studies topology partitioning, assigning disjoint pieces of the network topology across processors, as a technique to increase emulation capacity with increasing hardware resources. We develop methods to create partitions based on expected communication across the topology. Our evaluation methodology quantifies the communication overhead or efficiency of the resulting partitions. We implement and contrast three partitioning strategies in ModelNet, a large-scale network emulator, using different topologies and uniform communication patterns. Results show that standard graph partitioning algorithms can double the efficiency of the emulation for Internet-like topologies relative to random partitioning.
{"title":"Toward scaling network emulation using topology partitioning","authors":"K. Yocum, Ethan Eade, Julius Degesys, David Becker, J. Chase, Amin Vahdat","doi":"10.1109/MASCOT.2003.1240666","DOIUrl":"https://doi.org/10.1109/MASCOT.2003.1240666","url":null,"abstract":"Scalability is the primary challenge to studying large complex network systems with network emulation. This paper studies topology partitioning, assigning disjoint pieces of the network topology across processors, as a technique to increase emulation capacity with increasing hardware resources. We develop methods to create partitions based on expected communication across the topology. Our evaluation methodology quantifies the communication overhead or efficiency of the resulting partitions. We implement and contrast three partitioning strategies in ModelNet, a large-scale network emulator, using different topologies and uniform communication patterns. Results show that standard graph partitioning algorithms can double the efficiency of the emulation for Internet-like topologies relative to random partitioning.","PeriodicalId":344411,"journal":{"name":"11th IEEE/ACM International Symposium on Modeling, Analysis and Simulation of Computer Telecommunications Systems, 2003. MASCOTS 2003.","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123798096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-27DOI: 10.1109/MASCOT.2003.1240642
Mounire El Houmaidi, M. Bassiouni
In WDM all-optical networks, the deployment of wavelength converters improves the blocking performance. One solution is to equip every node in the network with converters (full wavelength conversion); however the cost and the technological limitations make it not practical. The alternative is to choose a subset of nodes and equip them with wavelength converters (sparse wavelength conversion). This paper makes the first known attempt to solve the sparse wavelength converters placement problem using the k-weighted minimum dominating set (k-WMDS) approach. To evaluate our proposed scheme under nonuniform traffic, we compared it against the well-known approach (referred to as k-BLK) of placing converters in nodes having the highest blocking percentage. The two algorithms were compared under different nonuniform traffic loads using network simulation with the U.S Long Haul and NSFNET topologies. For different values of the hop-distance parameter, k, the proposed k-WMDS algorithm has consistently given better blocking performance than k-BLK under the constraint that the number of converters in both algorithms is equal to the cardinality of the k-weighted minimum dominating set.
{"title":"k-weighted minimum dominating sets for sparse wavelength converters placement under nonuniform traffic","authors":"Mounire El Houmaidi, M. Bassiouni","doi":"10.1109/MASCOT.2003.1240642","DOIUrl":"https://doi.org/10.1109/MASCOT.2003.1240642","url":null,"abstract":"In WDM all-optical networks, the deployment of wavelength converters improves the blocking performance. One solution is to equip every node in the network with converters (full wavelength conversion); however the cost and the technological limitations make it not practical. The alternative is to choose a subset of nodes and equip them with wavelength converters (sparse wavelength conversion). This paper makes the first known attempt to solve the sparse wavelength converters placement problem using the k-weighted minimum dominating set (k-WMDS) approach. To evaluate our proposed scheme under nonuniform traffic, we compared it against the well-known approach (referred to as k-BLK) of placing converters in nodes having the highest blocking percentage. The two algorithms were compared under different nonuniform traffic loads using network simulation with the U.S Long Haul and NSFNET topologies. For different values of the hop-distance parameter, k, the proposed k-WMDS algorithm has consistently given better blocking performance than k-BLK under the constraint that the number of converters in both algorithms is equal to the cardinality of the k-weighted minimum dominating set.","PeriodicalId":344411,"journal":{"name":"11th IEEE/ACM International Symposium on Modeling, Analysis and Simulation of Computer Telecommunications Systems, 2003. MASCOTS 2003.","volume":"166 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123824088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-27DOI: 10.1109/MASCOT.2003.1240667
Ismail Ari, Bo Hong, E. L. Miller, S. Brandt, D. Long
A flash crowd is a surge in traffic to a particular Web site that causes the site to be virtually unreachable. We present a model of flash crowd events and evaluate the performance of various multilevel caching techniques suitable for managing these events. By using well-dispersed caches and with judicious choice of replacement algorithms we show reductions in client response times by as much as a factor of 25. We also show that these caches eliminate the server and network hot spots by distributing the load over the entire network.
{"title":"Managing flash crowds on the Internet","authors":"Ismail Ari, Bo Hong, E. L. Miller, S. Brandt, D. Long","doi":"10.1109/MASCOT.2003.1240667","DOIUrl":"https://doi.org/10.1109/MASCOT.2003.1240667","url":null,"abstract":"A flash crowd is a surge in traffic to a particular Web site that causes the site to be virtually unreachable. We present a model of flash crowd events and evaluate the performance of various multilevel caching techniques suitable for managing these events. By using well-dispersed caches and with judicious choice of replacement algorithms we show reductions in client response times by as much as a factor of 25. We also show that these caches eliminate the server and network hot spots by distributing the load over the entire network.","PeriodicalId":344411,"journal":{"name":"11th IEEE/ACM International Symposium on Modeling, Analysis and Simulation of Computer Telecommunications Systems, 2003. MASCOTS 2003.","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132864472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-27DOI: 10.1109/MASCOT.2003.1240640
Fengzhou Zheng, Nitin Garg, Sumeet Sobti, Chi Zhang, Russell E. Joseph, A. Krishnamurthy, Randolph Y. Wang
This paper is motivated by a simple question: what are the energy consumption characteristics of mobile storage alternatives? To answer this question, we are faced with a design space of multiple dimensions. Two important dimensions are the type of storage technologies and the type of file systems. In this paper, we explore some options along each of these two dimensions. We have constructed a logical-disk system, which can be configured to run on different storage technologies and to emulate the behavior of different file systems. As we explore these configuration options, we find that the energy behavior is determined by a complex interaction of three factors: the power management mechanism of the storage device, the distribution of idleness in the workload, and the file system strategies that attempt to exploit and bridge these first two factors.
{"title":"Considering the energy consumption of mobile storage alternatives","authors":"Fengzhou Zheng, Nitin Garg, Sumeet Sobti, Chi Zhang, Russell E. Joseph, A. Krishnamurthy, Randolph Y. Wang","doi":"10.1109/MASCOT.2003.1240640","DOIUrl":"https://doi.org/10.1109/MASCOT.2003.1240640","url":null,"abstract":"This paper is motivated by a simple question: what are the energy consumption characteristics of mobile storage alternatives? To answer this question, we are faced with a design space of multiple dimensions. Two important dimensions are the type of storage technologies and the type of file systems. In this paper, we explore some options along each of these two dimensions. We have constructed a logical-disk system, which can be configured to run on different storage technologies and to emulate the behavior of different file systems. As we explore these configuration options, we find that the energy behavior is determined by a complex interaction of three factors: the power management mechanism of the storage device, the distribution of idleness in the workload, and the file system strategies that attempt to exploit and bridge these first two factors.","PeriodicalId":344411,"journal":{"name":"11th IEEE/ACM International Symposium on Modeling, Analysis and Simulation of Computer Telecommunications Systems, 2003. MASCOTS 2003.","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125344992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-27DOI: 10.1109/MASCOT.2003.1240663
Qi Zhang, E. Smirni, G. Ciardo
We focus on service differentiation policies for Web servers where clients have different QoS requirements and the environment has large fluctuations in the client arrival and service patterns and in the QoS class mix. We propose an adaptive admission control mechanism that offers service differentiation among client classes and maximizes the effectiveness of the server's operation. Using actual traces from the 1998 World Cup web site, we conduct a detailed analysis of the proposed policy and show that it meets the performance challenges of a robust QoS policy.
{"title":"Profit-driven service differentiation in transient environments","authors":"Qi Zhang, E. Smirni, G. Ciardo","doi":"10.1109/MASCOT.2003.1240663","DOIUrl":"https://doi.org/10.1109/MASCOT.2003.1240663","url":null,"abstract":"We focus on service differentiation policies for Web servers where clients have different QoS requirements and the environment has large fluctuations in the client arrival and service patterns and in the QoS class mix. We propose an adaptive admission control mechanism that offers service differentiation among client classes and maximizes the effectiveness of the server's operation. Using actual traces from the 1998 World Cup web site, we conduct a detailed analysis of the proposed policy and show that it meets the performance challenges of a robust QoS policy.","PeriodicalId":344411,"journal":{"name":"11th IEEE/ACM International Symposium on Modeling, Analysis and Simulation of Computer Telecommunications Systems, 2003. MASCOTS 2003.","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127811246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-27DOI: 10.1109/MASCOT.2003.1240658
Arkaitz Bitorika, Mathieu Robin, M. Huggard
Over the last decade numerous active queue management (AQM) schemes have been proposed in the literature. Many of these studies have been directed towards improving congestion control in best-effort networks. However, there has been a notable lack of standardised performance evaluation of AQM schemes. A rigorous study of the influence of parameterisation on specific schemes and the establishment of common comparison criteria is essential for objective evaluation of the different approaches. A framework for the detailed evaluation of AQM schemes is described in this paper. This provides a deceptively simple user interface whilst maximally exploiting relevant features of the NS2 simulator. Traffic models and network topologies are carefully chosen to characterise the target simulation environment. The credibility of the results obtained is enhanced by vigilant treatment of the simulation data. The impact of AQM schemes on global network performance is assessed using five carefully selected metrics. Thus, a comprehensive evaluation of AQM schemes may be achieved using the proposed framework.
{"title":"An evaluation framework for active queue management schemes","authors":"Arkaitz Bitorika, Mathieu Robin, M. Huggard","doi":"10.1109/MASCOT.2003.1240658","DOIUrl":"https://doi.org/10.1109/MASCOT.2003.1240658","url":null,"abstract":"Over the last decade numerous active queue management (AQM) schemes have been proposed in the literature. Many of these studies have been directed towards improving congestion control in best-effort networks. However, there has been a notable lack of standardised performance evaluation of AQM schemes. A rigorous study of the influence of parameterisation on specific schemes and the establishment of common comparison criteria is essential for objective evaluation of the different approaches. A framework for the detailed evaluation of AQM schemes is described in this paper. This provides a deceptively simple user interface whilst maximally exploiting relevant features of the NS2 simulator. Traffic models and network topologies are carefully chosen to characterise the target simulation environment. The credibility of the results obtained is enhanced by vigilant treatment of the simulation data. The impact of AQM schemes on global network performance is assessed using five carefully selected metrics. Thus, a comprehensive evaluation of AQM schemes may be achieved using the proposed framework.","PeriodicalId":344411,"journal":{"name":"11th IEEE/ACM International Symposium on Modeling, Analysis and Simulation of Computer Telecommunications Systems, 2003. MASCOTS 2003.","volume":"83 12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127971989","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-27DOI: 10.1109/MASCOT.2003.1240674
Elizabeth Varki, A. Merchant, Jianzhang Xu, Xiaozhou Qiu
All enterprise storage systems depend on disk arrays to satisfy their capacity, reliability, and availability requirements. Performance models of disk arrays are useful in understanding the behavior of these storage systems and predicting their performance. We extend prior disk array modeling work by developing an analytical disk array model that incorporates the effects of workload sequentiality, read-ahead caching, write-back caching, and other complex optimizations incorporated into most disk arrays. The model is computationally simple and scales easily, making it potentially useful to performance engineers.
{"title":"An integrated performance model of disk arrays","authors":"Elizabeth Varki, A. Merchant, Jianzhang Xu, Xiaozhou Qiu","doi":"10.1109/MASCOT.2003.1240674","DOIUrl":"https://doi.org/10.1109/MASCOT.2003.1240674","url":null,"abstract":"All enterprise storage systems depend on disk arrays to satisfy their capacity, reliability, and availability requirements. Performance models of disk arrays are useful in understanding the behavior of these storage systems and predicting their performance. We extend prior disk array modeling work by developing an analytical disk array model that incorporates the effects of workload sequentiality, read-ahead caching, write-back caching, and other complex optimizations incorporated into most disk arrays. The model is computationally simple and scales easily, making it potentially useful to performance engineers.","PeriodicalId":344411,"journal":{"name":"11th IEEE/ACM International Symposium on Modeling, Analysis and Simulation of Computer Telecommunications Systems, 2003. MASCOTS 2003.","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133707209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-27DOI: 10.1109/MASCOT.2003.1240660
S. Merugu, Sridhar Srinivasan, E. Zegura
In the past few years, there has been intense interest in designing and studying peer-to-peer networks. Many initial measurement studies on current deployed peer-to-peer networks attempted to understand their performance. However, the large size and complex nature of these networks make it difficult to analyze their properties. Simulation of these peer-to-peer networks enables a methodical evaluation and analysis of their performance. However, to our knowledge, there is no tool for simulating different peer-to-peer network protocols for a comparative study. We present p-sim: a tool that can simulate peer-to-peer networks on top of representative Internet topologies, p-sim has several capabilities to provide an accurate model of real-world peer-to-peer networks, p-sim can scale to thousands of nodes and is extensible to simulate new peer-to-peer network protocols. In this paper, we discuss the capabilities of p-sim, its user-interface and two case-studies.
{"title":"P-sim: a simulator for peer-to-peer networks","authors":"S. Merugu, Sridhar Srinivasan, E. Zegura","doi":"10.1109/MASCOT.2003.1240660","DOIUrl":"https://doi.org/10.1109/MASCOT.2003.1240660","url":null,"abstract":"In the past few years, there has been intense interest in designing and studying peer-to-peer networks. Many initial measurement studies on current deployed peer-to-peer networks attempted to understand their performance. However, the large size and complex nature of these networks make it difficult to analyze their properties. Simulation of these peer-to-peer networks enables a methodical evaluation and analysis of their performance. However, to our knowledge, there is no tool for simulating different peer-to-peer network protocols for a comparative study. We present p-sim: a tool that can simulate peer-to-peer networks on top of representative Internet topologies, p-sim has several capabilities to provide an accurate model of real-world peer-to-peer networks, p-sim can scale to thousands of nodes and is extensible to simulate new peer-to-peer network protocols. In this paper, we discuss the capabilities of p-sim, its user-interface and two case-studies.","PeriodicalId":344411,"journal":{"name":"11th IEEE/ACM International Symposium on Modeling, Analysis and Simulation of Computer Telecommunications Systems, 2003. MASCOTS 2003.","volume":"241 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133853638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-27DOI: 10.1109/MASCOT.2003.1240676
B. Ciciani, F. Quaglia, P. Romano, D. Dias
Reverse proxy caches are used to provide scalability and improved latency to popular sites on the Web. In this paper we provide analytical performance models for distributed reverse proxy cache architectures, and study the trade-offs between various design alternatives. Specifically, we consider static and dynamic assignment of proxy cache nodes to Web sites, with different levels of sharing of proxy caches among Web sites. Innovative modeling contributions have been introduced to handle real design constraints, such as bounded cache size and bounded processing power, and different characteristics related to the hosted objects, including reference rates, popularity distributions and update rates. In the analysis we have modeled both system steady state as well as transient interaction between proxy sites and Web sites. We have found different trade-offs between various design alternatives depending on characteristics of the Web site workloads.
{"title":"Analysis of design alternatives for reverse proxy cache providers","authors":"B. Ciciani, F. Quaglia, P. Romano, D. Dias","doi":"10.1109/MASCOT.2003.1240676","DOIUrl":"https://doi.org/10.1109/MASCOT.2003.1240676","url":null,"abstract":"Reverse proxy caches are used to provide scalability and improved latency to popular sites on the Web. In this paper we provide analytical performance models for distributed reverse proxy cache architectures, and study the trade-offs between various design alternatives. Specifically, we consider static and dynamic assignment of proxy cache nodes to Web sites, with different levels of sharing of proxy caches among Web sites. Innovative modeling contributions have been introduced to handle real design constraints, such as bounded cache size and bounded processing power, and different characteristics related to the hosted objects, including reference rates, popularity distributions and update rates. In the analysis we have modeled both system steady state as well as transient interaction between proxy sites and Web sites. We have found different trade-offs between various design alternatives depending on characteristics of the Web site workloads.","PeriodicalId":344411,"journal":{"name":"11th IEEE/ACM International Symposium on Modeling, Analysis and Simulation of Computer Telecommunications Systems, 2003. MASCOTS 2003.","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115717822","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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