The large-scale behavior of routing in the Internet has gone virtually without any formal study, the exceptions being Chinoy's analysis of the dynamics of Internet routing information [Ch93], and recent work, similar in spirit, by Labovitz, Malan and Jahanian [LMJ97]. We report on an analysis of 40,000 end-to-end route measurements conducted using repeated “traceroutes ” between 37 Internet sites. We analyze the routing behavior for pathological conditions, routing stability, and routing symmetry. For pathologies, we characterize the prevalence of routing loops, erroneous routing, infrastructure failures, and temporary outages. We find that the likelihood of encountering a major routing pathology more than doubled between the end of 1994 and the end of 1995, rising from 1.5 % to 3.3%. For routing stability, we define two separate types of stability, “prevalence, ” meaning the overall likelihood that a particular route is encountered, and “persistence, ” the likelihood that a route remains unchanged over a long period of time. We find that Internet paths are heavily dominated by a single prevalent route, but that the time periods over which routes persist show wide variation, ranging from seconds up to days. About 2/3's of the Internet paths had routes persisting for either days or weeks. For routing symmetry, we look at the likelihood that a path through the Internet visits at least one different city in the two directions. At the end of 1995, this was the case half the time, and at least one different autonomous system was visited 30 % of the time.

Historically, the Internet has been woefully under-measured and under-instrumented. The problem is only getting worse with the network's ever-increasing size. We discuss the goals and requirements for building a "measurement infrastructure " for the Internet, in which a collection of measurement "platforms" cooperatively measure the properties of Internet paths and clouds by exchanging test traffic among themselves. The key emphasis of the architecture, which forms the underpinnings of the National Internet Measurement Infrastructure (NIMI) project, is on tackling problems related to scale. Consequently, the architecture emphasizes decentralized control of measurements; strong authentication and security; mechanisms for both maintaining tight administrative control over who can perform what measurements using which platforms, and delegation of some forms of measurement as a site's measurement policy permits; and simple configuration and maintenance of platforms. 1 Introduction Histori...

There is much interest in using network measurements for both modeling and operational purposes. In this paper we focus on the fundamental question of the stationarity of such measurements. That is, to what extent are past measurements a good predictor of the future? We used the NIMI infrastructure and a set of public traceroute servers to capture large measurement datasets of three quantities: routing, packet loss, and TCP throughput. We apply statistical tests to attempt to develop sound characterizations of the stationarity of these data sets, and discuss several types of nonstationarity. 1 Introduction In recent years there has been a surge of interest in network measurements. These measurements have deepened our understanding of network behavior and led to more accurate and qualitatively different models of network traffic. Network measurements are also used operationally by various protocols to guide network usage. For instance, RLM [MJV96] and equation-based congestion control...

The Internet's tremendous growth represents a triumph of standardization, since it is only through standardization that so many different networks using so many different designs can smoothly exchange data. The standardization of Internet measurement, however, has not matched the explosive growth of the network as a whole. Even such basic notions as how to measure the throughput or delay along an Internet path lack a standardized framework. Instead it has become increasingly difficult to diagnose problems or determine whether one is receiving promised performance. In this paper we outline how a measurement framework might be developed to support Internet diagnosis and performance evaluation. We propose terminology to use in defining standards, including the key notions of metric as the fundamental property we wish to measure, methodology as a way to attempt to measure the property, and measurement as the result of a specific application of a methodology. We develop a basic contrast be...

Abstract—Formally, the Internet inter-domain routing system is a collection of networks, their policies, peering relationships and organizational affiliations, and the addresses they advertize. It also includes components like Internet exchange points. By its very definition, each and every aspect of this system is impacted by BGP, the de-facto standard inter-domain routing protocol. The element of this inter-domain routing system that has attracted the single-most attention within the research community has been the “inter-domain topology”. Unfortunately, almost from the get go, the vast majority of studies of this topology, from definition, to measurement, to modeling and analysis, have ignored the central role of BGP in this problem. The legacy is a set of specious findings, unsubstanciated claims, and ill-conceived ideas about the Internet as a whole. By presenting a BGP-focused state-of-the-art treatement of the aspects that are critical for a rigorous study of this inter-domain topology, we de-mythify in this paper many “controversial” observations reported in the existing literature. At the same time, we illustrate the benefits and richness of new scientific approaches to measuring, modeling, and analyzing the interdomain topology that are faithful to the BGP-specific nature of this problem domain. Index Terms—Internet topology, modeling, BGP, routing measurements, inference limitations

Network dimensioning is an important issue to provide stable and QoS--rich communication services. A reliable estimation of bandwidths of links between the end--to--end path is a first step towards the network dimensioning. Pathchar is one of such tools for the bandwidth estimation for every link between two end hosts. However, pathchar still has several problems. If unexpectedly large errors are included or if route alternation is present during the measurement, the obtained estimation is much far from the correct one. We investigate the method to eliminate those errors in estimating the bandwidth. To increase the reliability on the estimation, the confidence interval for the estimated bandwidth is important. For this purpose, two approaches, parametric and nonparametric approaches, are investigated to add the confidence intervals. Another important issue is the method for controlling the measurement period. If the link is stable, small measurement data is sufficient. On the other hand, if the data is not sufficient, many measurements is necessary to obtain an accurate and reliable estimation. In this paper, we propose a measurement method to adaptively control the number of measurement data sets.

IP addresses distribution in Internet and its application on reduction methods for IP alias resolution