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How Reliable Is Cable Internet? Here’s How Our Networks Are Performing

How Reliable Is Cable Internet? Here’s How Our Networks Are Performing

Mark Walker
Vice President, Technology Policy

Jul 13, 2020

Starting in mid-March, the world experienced a sudden surge in internet usage driven by the widespread COVID-19 stay-at-home orders that caused many of us to switch to working and studying at home in a matter of days. Cable broadband networks not only withstood this sudden surge in internet usage; they excelled. For example, for the week of June 27–July 4, 99.9 percent of U.S. cable broadband users saw no material impact on customer experience. Looking to the future, cable networks are also well-positioned to remain ahead of sustained increases in consumer demand. Although internet usage appears to have plateaued recently, CableLabs and the broader cable industry continue to develop further network advancements to ensure that internet performance stays well ahead of even the most demanding home users’ needs for years to come.

Internet Usage During COVID-19 and Cable Broadband Services 

Network monitoring provider OpenVault reveals just how much home internet usage jumped over the past few months:

  • In the United States, average daily downstream consumption from 9 a.m. to 5 p.m. in the first week of April totaled about 6.35 GB per household, up 42 percent from 4.46 GB in January. Upstream average usage during business hours rose to 0.39 GB, up 83 percent compared with 0.22 GB in January.
  • Worldwide, looking at a sample of 500 fixed, mobile and Wi-Fi network providers, networking equipment provider Sandvine found that overall traffic increased 40 percent between February 1 and April 19. It also found that upstream traffic rose 121 percent during this period.

Even considering these dramatic increases, home internet use remains heavily asymmetrical. The amount of data transmitted to the home (downstream) vastly outweighs the amount of data transmitted from the home (upstream). This is driven by the continued use of video streaming services (e.g., Netflix, YouTube) that require substantial amounts of data to be transmitted to the home to enable the user to view a movie, TV show or other video. These applications require very little data transmitted from the home.

Two-way video collaboration tools (e.g., Zoom, Microsoft Teams) do require more data to be transmitted from the home (upstream) in comparison with video streaming services due to two-way audio and video functionality. Even with the increased use of these collaboration tools, upstream data transmissions remain well below a tenth of total data transmitted over home internet connections.

The predominance of downstream use is further confirmed in the detailed examination of broadband use from a top-tier North American cable broadband operator, as set forth in Figures 1 and 2 below. Over the past 8 years, the proportion of downstream traffic has increased and plateaued at roughly 92–94 percent of total traffic at peak. Looking more closely at the most recent 5 months illustrates the rapid increase in internet use due to COVID-19. Even with upstream increasing at a faster rate than downstream, upstream use at peak maxed out at only 9 percent of total traffic, as illustrated in Figure 2. Additional metrics, trends and observations on cable internet usage can be found on NCTA’s COVID-19 Dashboard.

How Reliable Is Cable Internet? Here’s How Our Networks Are Performing, Figure 1

Figure 1: 2012 through June 2020, Average Downstream and Upstream Peak Use (kbps and %) per Subscriber from a Top-Tier North American Cable Broadband Operator

How Reliable Is Cable Internet? Here’s How Our Networks Are Performing, Figure 2

Figure 2: Mid-February 2020 through June 2020, Average Downstream and Upstream Peak Use (kbps and %) per Subscriber from a Top-Tier North American Cable Broadband Operator

Cable Broadband’s Outlook Is Healthy

The asymmetric design of cable’s internet service tiers accurately matches how consumers have been using the internet, even with the increased use during stay-at-home orders. This is important both to ensure a high-quality user experience and to efficiently allocate available network capacity. Cable operators continually monitor their networks and engineer them to accommodate significant fluctuations. There are indications that these increased levels of usage will be foundational as new use cases emerge and as a significant segment of the population continues to work and learn from home. For example, many companies have found that their remote workers maintained or even improved productivity—so much so that they may make the arrangement permanent.

Cable network technology, more formally known as Data Over Cable Service Interface Specification (DOCSIS®), has the flexibility and performance capabilities to handle further increases in consumer demand in both downstream and upstream data transmissions. With DOCSIS 3.1 technology, the current widely deployed version of cable network technology, cable operators are making gigabit services broadly available. For example, cable gigabit services are now available to 80 percent of U.S. housing units.

And there are more performance enhancements on the horizon with the recently released DOCSIS 4.0 specification, which will readily enable multi-gigabit internet services. In addition, the 10G platform provides increased reliability, enhanced security and reduced latency.

Taking a peek into the future, cable broadband networks have not only excelled in the initial surge in internet usage caused by the COVID-19 pandemic, but they will be ready for the potential long-term changes in consumer behavior that will drive increased internet usage. To learn more about the technologies that power cable’s broadband internet services today and into the future, click the button below.

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