The Growing Importance of Being Always On -- A first look at the reliability of broadband Internet access

Zachar S. Bischof*, Fabián E. Bustamante* and Nick Feamster†.
To appear in Proc. of TPRC, September 2018.
(*) Northwestern University (†) Princeton University

EECS Department
Northwestern University
Evanston, IL 60201, USA
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Broadband availability and performance continue to improve rapidly, spurred by both government and private investment and motivated by the recognized social and economic benefits of connectivity. A recent ITU ``State of Broadband'' reports that there are over 60 countries where fixed or mobile broadband penetration is above 25% and more than 70 countries where the majority of the population is online. According to Akamai's ``State of the Internet'' report, over the last four years, the top four countries in terms of average connection speed have nearly doubled their capacity.

Although providing access and sufficient capacity remains a challenge in many parts of the world, in most developed countries, broadband providers are offering sufficiently high capacities to encourage consumers to migrate services for entertainment, communication and home monitoring to over-the-top (OTT) alternatives. According to a recent survey, nearly 78% of U.S. broadband households subscribe to an OTT video service. Enterprises are following the same path, with over one-third opting to use VoIP phones instead of landline ones.

The proliferation of high-capacity access and the migration to OTT services have raised users' expectations of service reliability. A recent survey on consumer experience by the UK Office of Communication (Ofcom) ranks reliability first--- higher than even the speed of connection ---as the main reason for customer complaints. Our empirical study of access-ISP outages and user demand corroborates these observations, showing the effects of low reliability on user behavior, as captured by their demand on the network. Researchers and regulators alike have also recognized the need for clear standards and a better understanding of the role that service reliability plays in shaping the behavior of broadband users. Despite its growing importance, both the reliability of broadband services and potential ways to improve on it have received scant attention from the research community.

In this paper, we introduce an approach for characterizing broadband reliability using data collected by the many emerging national efforts to study broadband (in over 30 countries and apply this approach to the data gathered by the Measuring Broadband America (MBA) project, which is operated by the United States Federal Communications Commission (FCC). We show, among other findings, that current broadband services deliver an average availability of at most two nines (99%), with an average annual downtime of 17.8 hours. Motivated by our findings, we quantify the potential benefits of multihomed broadband access and study its feasibility as a solution for increasing reliability. Using the FCC MBA dataset and measurements collected by over 6,000 end-host vantage points in 75 countries, we show that multihoming the access link at the home gateway with two different providers adds two nines of service availability, matching the minimum four nines (99.99%) required by the FCC for the public switched telephone network (PSTN).