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Patterns Of Buffer Overflow In A Class Of Queues With Long Memory In The Input Stream
 Ann. Appl. Probab
, 1997
"... . We study the time it takes until a a fluid queue with a finite, but large, holding capacity reaches the overflow point. The queue is fed by an on/off process, with a heavy tailed on distribution, which is known to have long memory. It turns out that the expected time until overflow, as a function ..."
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Cited by 30 (9 self)
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. We study the time it takes until a a fluid queue with a finite, but large, holding capacity reaches the overflow point. The queue is fed by an on/off process, with a heavy tailed on distribution, which is known to have long memory. It turns out that the expected time until overflow, as a function of capacity L, increases only polynomially fast, and so overflows happen much more often than in the "classical" light tailed case, where the expected overflow time increases as an exponential function of L. Moreover, we show that in the heavy tailed case, overflows are basically caused by single huge jobs. An implication is that the usual GI=G=1 queue with finite but large holding capacity and heavy tailed service times, will overflow about equally often no matter how much we increase the service rate. We also study the time until overflow for queues fed by a superposition of k iid. on/off processes with a heavy tailed on distribution, and show the benefit of pooling the system resources a...
A Performance Study of Internet Web Servers
"... The phenomenal growth in popularity of the WorldWide Web (WWW or "the Web") has made WWW traffic the fastest growing component of network packet and byte traffic on the NSFNET backbone. This growth has triggered much recent research activity aimed at improving Web performance and scalability: reduc ..."
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Cited by 18 (1 self)
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The phenomenal growth in popularity of the WorldWide Web (WWW or "the Web") has made WWW traffic the fastest growing component of network packet and byte traffic on the NSFNET backbone. This growth has triggered much recent research activity aimed at improving Web performance and scalability: reducing the volume of network traffic produced by Web clients and servers by using file/document caching, and reducing the latency for WWW users by using improved protocols for Web interaction. Fundamental to the goal of improving WWW performance is an understanding of WWW workloads. This thesis presents a workload characterization study for WorldWide Web servers. Six different data sets are used in this study: three from academic (i.e., university) environments, two from scientific research organizations, and one from a commercial Internet provider. These data sets represent three different orders of magnitude in server activity, and two different orders of magnitude in time duration, ranging...
Why NonLinearities Can Ruin The Heavy Tailed Modeler's Day
"... . A heavy tailed time series that can be expressed as an infinite order moving average has the property that the sample autocorrelation function (acf) at lag h, converges in probability to a constant ae(h) despite the fact that the mathematical correlation typically does not exist. A simple bilinear ..."
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Cited by 16 (8 self)
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. A heavy tailed time series that can be expressed as an infinite order moving average has the property that the sample autocorrelation function (acf) at lag h, converges in probability to a constant ae(h) despite the fact that the mathematical correlation typically does not exist. A simple bilinear model considered by Davis and Resnick (1996) has the property that the sample autocorrelation function at lag h converges in distribution to a nondegenerate random variable. Examination of various data sets exhibiting heavy tailed behavior reveals that the sample correlation function typically does not behave like a constant. Usually, the sample acf of the first half of the data set looks considerably different than the sample acf of the second half. A possible explanation for this acf behavior is the presence of nonlinear components in the underlying model and this seems to imply that infinite order moving average models and in particular ARMA models do not adequately capture dependency s...
Stability and Performance Analysis of HIPERLAN
 Proc. IEEE INFOCOM ’98
, 1998
"... . This paper thoroughly analyses the HIPERLAN MAC protocol, which is a standard for Wireless Local Area Networks (WLANs) defined by the European Telecommunications Standards Institute (ETSI). Since the HIPERLAN MAC protocol belongs to the class of Carrier Sensing Multiple Access with Collision Avoid ..."
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Cited by 14 (0 self)
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. This paper thoroughly analyses the HIPERLAN MAC protocol, which is a standard for Wireless Local Area Networks (WLANs) defined by the European Telecommunications Standards Institute (ETSI). Since the HIPERLAN MAC protocol belongs to the class of Carrier Sensing Multiple Access with Collision Avoidance (CSMA/CA), in the first part of the paper we analyze the HIPERLAN stability problem. In the second part we present an in depth performance analysis, by simulation, of the HIPERLAN MAC protocol. The analysis is performed by considering data traffic patterns (hereafter advanced data traffic) which have a very similar shape to traffic generated by WWW applications. Furthermore, in the analysis we consider Poissonian data traffic too. Our conclusion is that the HIPERLAN MAC protocol performs satisfactorily, although performance measures with advanced traffic are worse than the corresponding performance measures with Poissonian traffic. Furthermore, we broadened our analysis to include the i...
System Support for Scalable and Fault Tolerant Internet Services
 IN IFIP INTERNATIONAL CONFERENCE ON DISTRIBUTED SYSTEMS PLATFORMS AND OPEN DISTRIBUTED PROCESSING (MIDDLEWARE '98), LAKE DISTRICT
, 1998
"... Over the past few years, we have seen the proliferation of Internetbased services ranging from search engines and map services to videoondemand servers. All of these kinds of services need to be able to provide guarantees of availability and scalability to their users. With millions of users on t ..."
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Cited by 14 (8 self)
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Over the past few years, we have seen the proliferation of Internetbased services ranging from search engines and map services to videoondemand servers. All of these kinds of services need to be able to provide guarantees of availability and scalability to their users. With millions of users on the Internet today, these services must have the capacity to handle a large number of clients and remain available even in the face of extremely high load. In this paper, we present a generic architecture for supporting such Internet applications. We provide a substrate for Scalable Network Services (SNS), on top of which application developers can design their services without worrying about the details of service management. We back our design with three realworld services: a web distillation proxy, a proxybased webbrowser for PDAs, and an MBone archive server.
SelfSimilar Communication Models And Very Heavy Tails
, 1998
"... Several studies of file sizes either being downloaded or stored in the world wide web have commented that tails can be so heavy that not only are variances infinite, but so are means. Motivated by this fact, we study the infinite node Poisson model under the assumption that transmission times are h ..."
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Cited by 14 (5 self)
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Several studies of file sizes either being downloaded or stored in the world wide web have commented that tails can be so heavy that not only are variances infinite, but so are means. Motivated by this fact, we study the infinite node Poisson model under the assumption that transmission times are heavy tailed with infinite mean. The model is unstable but we are able to provide growth rates. Selfsimilar but nonstationary Gaussian process approximations are provided for the number of active sources, cumulative input, buffer content and time to buffer overflow.
Lognormal and Pareto distributions in the Internet
 Comput. Commun
, 2005
"... Numerous studies have reported longtailed distributions for various network metrics, including file sizes, transfer times, and burst lengths. We review techniques for identifying longtailed distributions based on a sample, propose a new technique, and apply these methods to datasets used in previo ..."
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Cited by 11 (0 self)
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Numerous studies have reported longtailed distributions for various network metrics, including file sizes, transfer times, and burst lengths. We review techniques for identifying longtailed distributions based on a sample, propose a new technique, and apply these methods to datasets used in previous reports. We find that the evidence for long tails is inconsistent, and that lognormal and other nonlongtailed models are usually sufficient to characterize network metrics. We discuss the implications of this result for current explanations of selfsimilarity in network traffic.
Empirical Testing Of The Infinite Source Poisson Data Traffic Model
, 2000
"... The infinite source Poisson model is a fluid queue approximation of network data transmission that assumes that sources begin constant rate transmissions of data at Poisson time points for random lengths of time. This model has been a popular one as analysts attempt to provide explanations for obser ..."
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Cited by 10 (3 self)
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The infinite source Poisson model is a fluid queue approximation of network data transmission that assumes that sources begin constant rate transmissions of data at Poisson time points for random lengths of time. This model has been a popular one as analysts attempt to provide explanations for observed features in telecommunications data such as selfsimilarity, long range dependence and heavy tails. We survey some features of this model in cases where transmission length distributions have (a) tails so heavy that means are infinite, (b) heavy tails with finite mean and infinite variance and (c) finite variance. We survey the selfsimilarity properties of various descriptor processes in this model and then present analyses of four data sets which show that certain features of the model are consistent with the data while others are contradicted. The data sets are 1) the Boston University 1995 study of web sessions, 2) the UC Berkeley home IP HTTP data collected in November 1996, 3) tr...
Traffic selfsimilarity
 In IEEE International Conference on Telecommunications (ICT) Tutorial
, 2001
"... The unifying concept underlying fractals, chaos and power laws is selfsimilarity. Selfsimilarity, or invariance against changes in scale or size, is an attribute of many laws of nature and innumerable phenomena in the world around us. Selfsimilarity is, in fact, one of the decisive symmetries tha ..."
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Cited by 8 (0 self)
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The unifying concept underlying fractals, chaos and power laws is selfsimilarity. Selfsimilarity, or invariance against changes in scale or size, is an attribute of many laws of nature and innumerable phenomena in the world around us. Selfsimilarity is, in fact, one of the decisive symmetries that shapes our universe and our efforts to comprehend it.
Impact of NonPoisson Arrival Sequences for Call Admission Algorithms With and Without Delay
 in Proceedings of IEEE GLOBECOM
, 1996
"... New networking technologies such as ATM can carry a wide variety of traffic  voice, video, and data  over a single digital network. Since some of these services depend on bandwidth guarantees, the network should employ call admission algorithm to limit congestion. Call admission includes making ..."
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Cited by 8 (3 self)
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New networking technologies such as ATM can carry a wide variety of traffic  voice, video, and data  over a single digital network. Since some of these services depend on bandwidth guarantees, the network should employ call admission algorithm to limit congestion. Call admission includes making intelligent decisions about whether to accept a call, and if so, when to schedule it, and how to route it. Challenges in the design of such algorithms include high bandwidth requirements and the bursty nature of call arrivals. Recent empirical studies of traffic measurements from a variety of networks have demonstrated that characteristics of network traffic are nonpoisson. In particular, connection arrivals are much burstier than Poisson processes would predict; they actually show evidence of selfsimilarity behavior. In this paper we show that bursty traffic poses a significant challenge to existing call admission algorithms. To cope with bursty traffic and high bandwidth demands we sugg...