As Americans stay home to thwart the invisible threat of a virus lurking beyond their windows, they’ve become even more dependent upon something else they cannot see or feel: the Internet. US data networks - an intricate system of cables and towers and signals weaving throughout our country - are being put to the ultimate test in a nationwide work-from-home experiment that hinges entirely on these networks’ health and adaptability.

As residents shelter in place to stop the spread of the coronavirus, the surge in demand that Internet providers would expect to see gradually over the course of an entire year has instead hit in a matter of weeks. That’s because of all the work-from-home applications, calls and texts to check in with loved ones, Netflix binge-watching and virtual exercise classes and doctor’s visits. AT&T Inc reported that traffic on its core network was up 23% on April 5, from a comparable day in February. Comcast Corp said its peak traffic jumped more than 30% in March, and in some larger metropolitan areas, such as Chicago and San Francisco, it climbed as much as 60%. While streaming-video consumption is on the rise, data usage for gaming has more than doubled, according to Verizon Communications Inc.

It raises the question, how are these are these crucial networks faring, and will they be able to keep handling this kind of a load? The answer is complicated and even more so the longer the pandemic persists. But so far - as anyone fortunate enough to be able to work remotely and stream Netflix can attest - things seem to be going OK.

"These networks are holding up pretty well to the onslaught of traffic demand that they've been subject to,” Steve Alexander, chief technology officer at Ciena Corp, said during a virtual Zoom interview on April 6 - our very own test of the Internet’s capabilities during the new peak hours. (Ciena provides the underlying software and equipment used by network operators.)

Still, there’s no one official source for tracking the state of America’s digital connectivity. Ajit Pai, chairman of the US Federal Communications Commission, released a statement last week summarising the upbeat feedback he’s received from Internet providers. "It appears,” he said, that networks are performing fine, relying on the data disclosed by those companies. There are handy third-party sources such as Ookla and BroadbandNow; however, the different methodologies make it difficult to get a good read. For example, Ookla has shown a barely perceptible decline in average fixed broadband download speeds in the United States. But BroadbandNow has found that 88 of the top 200 cities have had "some degree of network degradation,” with 27 cities experiencing more significant declines.

Part of the problem is that nationwide averages aren’t practical when Internet infrastructure and reliability can vary immensely from one state or county to the next. Millions of Americans in rural towns still don’t have access to minimum download speeds of 25 megabits per second, as I noted last month. And even that probably isn’t sufficient for households using multiple devices simultaneously for data-intensive tasks such as watching Hulu and joining a work-video conference. Netflix and its ilk reduced picture quality in Europe to ease network congestion, but the United States hasn’t needed to resort to such actions.

Another issue is that connections tend to be measured in terms of download speeds, while upload speeds are much slower and are needed for things like video calls. That’s why it’s important to look at latency, the amount of time it takes a signal to travel, which can explain annoying buffering on streaming apps and lags in a FaceTime connection.

The unprecedented demand "is putting real stress on our networks, and with so much of modern life now dependent on these connections it is fair to ask how providers are managing this new demand,” US FCC Commissioner Jessica Rosenworcel said in a statement responding to questions sent to her office. "Getting a few reports using different methods from a handful of companies is useful, but it’s not enough.” Rosenworcel has called for the US FCC to issue daily updates on network status, just as it would during a hurricane or mass power outage, events that activate its Disaster Information Reporting System.

The US FCC has at least gotten Internet providers such as AT&T, Comcast and Verizon to sign onto its Keep Americans Connected Pledge, agreeing for 60 days not to terminate customers’ service if they’re unable to pay their bills. An emerging challenge could be the safety of employees who are essential to keeping these networks up and running. Like hospital and supermarket staff, their work hasn’t stopped.

As Ciena’s Alexander put it: "The network is there, kind of like air - it just works, until all of a sudden there’s an issue and you notice it.” For now, all we can really go by is the industry’s word. But you’ll know when there’s a problem.

This column does not necessarily reflect the opinion of Bloomberg LP and its owners.

Tara Lachapelle is a Bloomberg Opinion columnist covering the business of entertainment and telecommunications, as well as broader deals. She previously wrote an M&A column for Bloomberg News.

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