It would be an exaggeration to say that Netflix Inc. is the reason U.S. broadband networks were prepared to handle the extra traffic generated by the coronavirus crisis — but the yearslong shift to streaming was a key factor.

U.S. internet usage has surged in the days since the World Health Organization declared the coronavirus a global pandemic and federal and state leaders began encouraging many Americans to stay at home. Industry experts say investments to support bandwidth-intensive services such as high-definition streaming in recent years mean networks are so far standing up to the increased traffic, even as specific applications buckle under the strain.

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OpenVault LLC, which provides technology and industry analytics for broadband operators, said that in the week since COVID-19 was declared a pandemic, average daily broadband consumption rose to 15.46 GB, up from 12.19 GB per day in January. Based on this increase, OpenVault expects consumption for March will reach nearly 400 GB per subscriber, an increase of almost 11% over the 361 GB consumed per subscriber in January.

OpenVault CEO and founder Mark Trudeau noted in an interview that the month of January has traditionally been very similar in terms of usage as March.

"So it's a nice baseline to look at where we are in March and honestly what's changed since the beginning of March," he said.

As of March 25, Trudeau said, "The latest week shows 55% growth during weekday business hours in total gigabyte consumption. So huge growth during the business hours." He added that consumption during peak hours — 6 p.m. to 11 p.m. — has risen 22%.

So far, he said networks built for peak consumption "are easily handling" the rise in day-time usage.

Angelique Medina, director of product marketing at the network monitoring company ThousandEyes, said that the backbones of U.S. networks "are built out to handle a lot of capacity, and even the last mile, which is what a lot of consumers depend on, is not in bad shape".

Medina explained that the last mile networks operated by companies like Comcast Corp., Charter Communications Inc., AT&T Inc. and Verizon Communications Inc. — delivering communications services to consumer homes and businesses — were built to handle users streaming video on Google LLC's YouTube, Amazon.com Inc.'s Prime and Netflix, as well as video-chatting with friends.

That is not to say there have not been stress points in the country's broader digital infrastructure. One area where Medina has seen "choke points" is in applications from collaboration software providers like Zoom Video Communications Inc., Slack Technologies Inc., Microsoft Corp. and Cisco Systems Inc.

According to Verizon data released March 26, there has been a 47% increase week over week in the use of online collaboration tools on Verizon’s networks. Traffic using Virtual Private Networks, which allow people to create a secure connection over a public network, is also up 52% over a typical day, the company said.

Microsoft has seen "an unprecedented spike in Teams usage," according to a blog post from Jared Spataro, corporate vice president for Microsoft 365. Microsoft Teams grew from about 20 million users in November 2019 to 44 million in mid March, adding 12 million users in just a week, Spataro said.

Cisco has seen the number of meetings it hosts on the company's WebEx collaboration platform grow from around 4 million a week to 4 million per day, according to Cisco spokesperson Taylor Hassman.

Zoom, Slack and other cloud-based applications all face the same challenges because those apps are housed on a relatively small number of data-center facilities, Medina said. While these are hyperscale, cloud-based datacenters that have huge amounts of network and computing capacity, they were not prepared for the sudden influx of millions of people suddenly working from home due to the coronavirus.

"They're struggling to catch up with demand. We hope to see a lot of that go away within the next week or two," Medina said.

451 Research analyst Michael Fratto, who focuses on the networks and data-processing infrastructure, said conferencing services like Zoom and WebEx face a "two-fold challenge." First, these services need enough servers or compute capacity to run a collaborative application at the level customers expect. Fratto said this challenge can be pretty easily and quickly solved. "They probably get the scale from a cloud provider. And bandwidth is cheap," he said.

The second and bigger challenge, he noted, is getting a scaled-up application to handle all those new members correctly so that users can be identified, authenticated and connected to the right meeting.

One major question is whether broadband consumption will go back down after the pandemic subsides. Trudeau does not think so.

"I do think that whatever that new normal ends up being once this crisis period is over will still be much higher broadband usage," the OpenVault CEO said, adding that we may see more people working from home long term.

This is in line with recent survey data from 451 Research. Based on 820 responses from decision-makers of public and private sector industries, The Voice of the Enterprise: Digital Pulse, Coronavirus Flash Survey March 2020, conducted March 10-19, found that 37.8% of respondents expect expanded work-from-home policies to remain in place long-term or become permanent in the wake of the pandemic.