METRICS

In this paper, we examine algorithms and data structures for the longest prefix match operation required for routing IP packets. Previous work, aimed at hardware implementations, has focused on quantifying worst case lookup time and memory usage. With ...

Recent efforts to add new services to the Internet have increased the interest in software-based routers that are easy to extend and evolve. This paper describes our experiences implementing a software-based router, with a particular focus on the main ...

In this paper we study the dynamic multi-path routing problem. We focus on an operating regime where traffic flows arrive at and depart from the network in a bursty fashion, and where the delays involved in link state advertisement may lead to "...

Soft Modems use the main processor to execute modem functions traditionally performed by hardware on the modem card. To function correctly, soft modems require that ongoing signal processing computations be performed on the host CPU in a timely manner. ...

This paper addresses algorithms for dynamically varying (scaling) CPU speed and voltage in order to save energy. Such scaling is useful and effective when it is immaterial when a task completes, as long as it meets some deadline. We show how to modify ...

Several recent studies have reported the phenomenon of "software aging", one in which the state of a software system degrades with time. This may eventually lead to performance degradation of the software or crash/hang failure or both. "Software ...

The increasing complexity of modern superscalar microprocessors makes the evaluation of new designs and techniques much more difficult. Fast and accurate methods for simulating program execution on realistic and hypothetical processor models are of ...

We discuss the relevance of fairness as a design objective for congestion control mechanisms in the Internet. Specifically, we consider a backbone network shared by a dynamic number of short-lived flows, and study the impact of bandwidth sharing on ...

In this paper we perform the statistical analysis of an Internet communication channel. Our study is based on a Hidden Markov Model (HMM). The channel switches between different states; to each state corresponds the probability that a packet sent by the ...

Traffic variables on an uncongested Internet wire exhibit a pervasive nonstationarity. As the rate of new TCP connections increases, arrival processes (packet and connection) tend locally toward Poisson, and time series variables (packet sizes, ...

In this paper we study the performance trade-offs between conventional cellular and multi-hop ad-hoc wireless networks. We compare through simulations the performance of the two network models in terms of raw network capacity, end-to-end throughput, end-...

We consider large cellular networks. The traffic entering the network is assumed to be correlated in both space and time. The space dependency captures the possible correlation between the arrivals to different nodes in the network, while the time ...

The IEEE 802.15 Wireless Personal Area Networks (WPAN) study group has been working on evolving a standard for short-range wireless connectivity between low complexity and low power devices operating within the personal operating space (POS). The ...

In this paper we develop a new predictive flow control scheme and analyze its performance. This scheme controls the non-real-time traffic based on predicting the real-time traffic. The goal of the work is to operate the network in a low congestion, high ...

We consider the problem of estimating buffer overflow probabilities when the statistics of the input traffic are not known and have to be estimated from measurements. We start by investigating the use of Markov-modulated processes in modeling the input ...

We consider the problem of designing a virtual topology to minimize electronic routing, that is, grooming traffic, in wavelength routed optical rings. We present a new framework consisting of a sequence of bounds, both upper and lower, in which each ...

The min-plus theory of greedy shapers has been developed after Cruz's results on the calculus of network delays. An example of greedy shaper is the buffered leaky bucket controller. The theory of greedy shapers establishes a number of properties; for ...

In this paper, we consider the performance analysis problem for a work conserving link with a large number of independent regulated inputs. For such a problem, we derive simple stochastic bounds under a general traffic constraint for the inputs. The ...

This paper studies the memory behavior of important Java workloads used in benchmarking Java Virtual Machines (JVMs), based on instrumentation of both application and library code in a state-of-the-art JVM, and provides structured information about ...

Multimedia applications are fast becoming one of the dominating workloads for modern computer systems. Since these applications normally have large data sets and little data-reuse, many researchers believe that they have poor memory behavior compared to ...

In this paper, we explore the use of fixed point methods to evaluate the performance of a large population of TCP flows traversing a network of routers implementing active queue management (AQM) such as RED (random early detection). Both AQM routers ...

This paper presents a model of the TCP Vegas congestion control mechanism as a distributed optimization algorithm. Doing so has three important benefits. First, it helps us gain a fundamental understanding of why TCP Vegas works, and an appreciation of ...

Robots are deployed by a Web search engine for collecting information from different Web servers in order to maintain the currency of its data base of Web pages. In this paper, we investigate the number of robots to be used by a search engine so as to ...

We report the results of a large-scale empirical study of web traffic. Our study is based on over 500 GB of TCP/IP protocol-header traces collected in 1999 and 2000 (approximately one year apart) from the high-speed link connecting The University of ...

WWW workload generators are used to evaluate web server performance, and thus have a large impact on what performance optimizations are applied to servers. However, current benchmarks ignore a crucial component: how these servers perform in the ...

We consider an M/M/1 queue in a semi-Markovian environment. The environment is modeled by a two-state semi-Markov process with arbitrary sojourn time distributions F₀(x) and F₁(x). When in state i = 0, 1, customers are generated according to a Poisson ...

The Shortest-Remaining-Processing-Time (SRPT) scheduling policy has long been known to be optimal for minimizing mean response time (sojourn time). Despite this fact, SRPT scheduling is rarely used in practice. It is believed that the performance ...

Exact as well as approximate analytical solutions for quantitative performance models of computer systems are usually obtained by performing a series of arithmetical operations on the input parameters of the model. However, especially during early ...

To evaluate the performance of a software design one must create a model of the software, together with the execution platform and configuration. Assuming that the "platform": (processors, networks, and operating systems) are specified by the designer, ...