In this paper, we empirically demonstrate the growing importance of reliability by measuring its effect on user behavior. We present an approach for broadband reliability characterization using data collected by many emerging national initiatives to study broadband and apply it to the data gathered by the Federal Communications Commission's Measuring Broadband America project. Motivated by our findings, we present the design, implementation, and evaluation of a practical approach for improving the reliability of broadband Internet access with multihoming.
Baltr = u @cite_48 presented a study of the reliability of four mobile broadband providers in Norway using the Nornet Edge dedicated infrastructure. This work illustrates the value of end-to-end measurements to identify failures and performance events not always captured by the operators' monitoring systems. Broadband reliability has received little attention until recently. @cite_67 discuss some of the challenges of characterizing reliability and their economic and policy implications and identify three different ways in which the reliability'' of broadband services can be measured: (1) the reliability of the service itself; (2) the reliability of network services offered by the ISP (e.g., DNS); and (3) the consistency of the service's performance. We focus on characterizing reliability in terms of the former two categories and leave the latter as future work.
@cite_48 @cite_67
1973981542 2276787602 2004203035 2139577842
Mobile broadband networks play an increasingly important role in society, and there is a strong need for independent assessments of their robustness and performance. A promising source of such information is active end-to-end measurements. It is, however, a challenging task to go from individual measurements to an assessment of network reliability, which is a complex notion encompassing many stability and performance related metrics. This paper presents a framework for measuring the user-experienced reliability in mobile broadband networks. We argue that reliability must be assessed at several levels, from the availability of the network connection to the stability of application performance. Based on the proposed framework, we conduct a large-scale measurement study of reliability in 5 mobile broadband networks. The study builds on active measurements from hundreds of measurement nodes over a period of 10 months. The results show that the reliability of mobile broadband networks is lower than one could hope: more than 20 of connections from stationary nodes are unavailable more than 10 minutes per day. There is, however, a significant potential for improving robustness if a device can connect simultaneously to several networks. We find that in most cases, our devices can achieve 99.999 ("five nines") connection availability by combining two operators. We further show how both radio conditions and network configuration play important roles in determining reliability, and how external measurements can reveal weaknesses and incidents that are not always captured by the operators' existing monitoring tools. With broadband availability now approaching universal service in the United States, the focus on broadband metrics is shifting toward the assessment of broadband performance. The initial focus has been on the measurement and reporting of the speeds achieved by broadband services. As we develop more comprehensive and, hopefully, more meaningful frameworks for characterizing, measuring, and evaluating broadband performance, one obvious measure of merit will be reliability. In a survey, consumers identified concerns about reliability as second only to speed in importance. Moreover, as our collective reliance on broadband as critical socio-economic infrastructure increases, and as a growing range of services move into the Internet, it is reasonable to expect that demand for reliable broadband service will increase. At the same time, the growth of streaming and interactive rich multimedia, the convergence of fixed and mobile services, and the evolution of the Internet services industry pose new challenges for developing appropriate reliability metrics. While the measurement of broadband availability or speeds and the appropriate interpretation of measurement data are not simple tasks, evaluating reliability is inherently much more complex and difficult. We present the first study of broadband services in their broader context, evaluating the impact of service characteristics (such as capacity, latency and loss), their broadband pricing and user demand. We explore these relationships, beyond correlation, with the application of natural experiments. Most efforts on broadband service characterization have so far focused on performance and availability, yet we lack a clear understanding of how such services are being utilized and how their use is impacted by the particulars of the market. By analyzing over 23-months of data collected from 53,000 end hosts and residential gateways in 160 countries, along with a global survey of retail broadband plans, we empirically study the relationship between broadband service characteristics, pricing and demand. We show a strong correlation between capacity and demand, even though subscribers rarely fully utilize their links, but note a law of diminishing returns with relatively smaller increases in demand at higher capacities. Despite the fourfold increase in global IP traffic, we find that user demand on the network over a three year period remained constant for a given bandwidth capacity. We exploit natural experiments to examine the causality between these factors. The reported findings represent an important step towards understanding how user behavior, and the market features that shape it, affect broadband networks and the Internet at large. A large and rapidly growing proportion of users connect to the Internet via residential broadband networks such as Digital Subscriber Lines (DSL) and cable. Residential networks are often the bottleneck in the last mile of today's Internet. Their characteristics critically affect Internet applications, including voice-over-IP, online games, and peer-to-peer content sharing delivery systems. However, to date, few studies have investigated commercial broadband deployments, and rigorous measurement data that characterize these networks at scale are lacking. In this paper, we present the first large-scale measurement study of major cable and DSL providers in North America and Europe. We describe and evaluate the measurement tools we developed for this purpose. Our study characterizes several properties of broadband networks, including link capacities, packet round-trip times and jitter, packet loss rates, queue lengths, and queue drop policies. Our analysis reveals important ways in which residential networks differ from how the Internet is conventionally thought to operate. We also discuss the implications of our findings for many emerging protocols and systems, including delay-based congestion control (e.g., PCP) and network coordinate systems (e.g., Vivaldi).