Yesterday’s corporate network design isn’t working for working from home

Multitudes are working from home. This changes how business' networks work.
Enlarge / Multitudes are working from home. This changes how business’ networks work.

Aurich Lawson / Getty Images

We’re 10 months into 2020, and businesses are still making adjustments to the new realities of large-scale telework (which, if you’re not in the IT biz, is just a fancy term for “working from not in the office”). In the Before Times, telework was an interesting idea that tech companies were just starting to seriously flirt with as a normal way of doing business—whereas now, most businesses large or small have a hefty fraction of their workforce staying home to work.

Unfortunately, making such a sweeping change to office workflow doesn’t just disrupt policies and expectations—it requires important changes to the technical infrastructure as well. Six months ago, we talked about the changes the people who work from home frequently need to make to accommodate telework; today, we’re going to look at the ongoing changes the businesses themselves need to make.

We’re going to need a bigger boat pipe

The most obvious problem that businesses have faced—and are continuing to face—with a greatly multiplied number of remote workers is the size of the company’s Internet connection. If you need a quarter—or half, or three quarters—of your workforce to remote in to work every day, you need enough bandwidth to accommodate them.

(Remember, when working from home, most people connect back to the office via VPN. That means all of the bits you’re moving around on your laptop while you’re at work are transiting through your office’s Internet connection via that VPN. So even though you’re at home, you’re almost certainly leaning on your work’s Internet.)

Smaller businesses are generally facing the worst of this particular problem. In most places, small businesses are still using residential-style asymmetrical Internet connections, typically with a 10:1 upload/download bandwidth ratio. When almost all of your workers are in the office, a connection with 10 times the downstream bandwidth makes sense, for the same reasons it does at most people’s homes—the majority of the content lives in the cloud, and the majority of the network throughput is downloaded, not uploaded.

This changes dramatically once you have a substantial fraction of the workplace working remotely. Now, the office itself—and its domain, file, and application servers—are “the cloud” from the perspective of your workforce, and while their home Internet connections still make sense—10:1 biased toward download—the office is badly out of whack. A 200 x 20Mbps connection looks a lot worse when you’re bottlenecking on the 20Mbps side of it for a half-hour at a time.

The problem is even worse than it appears at first glance.

In the charts at the top of this section, we can see a small business struggling with exactly this scenario. With roughly a third of the office’s workers working from home, the download utilization is dwarfed by the upload—despite the upload side of the pipe being a tenth the width of the download.

For about a half-hour in the afternoon, the 20Mbps upload is completely saturated, which brings everything to a halt—even the underutilized download pipe feels constrained, because it takes longer to get HTTPS requests and DNS requests out through the saturated upload side, before the downloads themselves can begin.

The problem is even worse than it appears at first glance: the reason that most of the day seems to plateau at closer to 10Mbps than 20Mbps isn’t lower demand from the workforce but, rather, lower supply from the ISP. During workdays, the ISP’s supposedly “20Mbps” upload pipe tends to saturate at only 10-12Mbps.

The only real fix for this problem is upgrading to a symmetrical Internet connection—even a relatively basic 100Mbps fiber connection would offer five to 10 times better throughput than the coaxial-cable network connection this and many other businesses are currently limited to. However, such a connection is often considerably more expensive.

Absent (or in addition to) the fiber, retraining employees to remote control office PCs instead of moving files back and forth across the VPN is one of the best ways to conserve bandwidth. An employee actively using a full-screen RDP session will typically consume between 10MiB and 25MiB per hour connected and working; the same employee downloading even a small CAD project or a few images could consume five to 10 times that much bandwidth in just a few minutes.

Traffic shaping—i.e., prioritizing packets based on what protocol they’re using, or where they’re going—can also help somewhat. But this tends to be more band-aid than cure. If 10 employees are each trying to download a 100MiB asset over a 20Mbps connection, you’re in for plenty of pain no matter how cleverly you’ve optimized your network flow.

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