What is Cloudflare, and why did it cause outages across the internet today?

By Emily Bary

As services like X and ChatGPT experienced disruptions, attention turned to Cloudflare, the $70 billion company that helps route network traffic behind the scenes

Cloudflare acknowledged the service disruptions on Tuesday but said a fix was in place.

Cloudflare is known for operating behind the scenes, but it amassed some name recognition for the wrong reasons on Tuesday.

The company suffered a service issue that impacted multiple customers, sparked error messages and affected connections to application programming interfaces, or APIs. Cloudflare (NET) later said it implemented a fix.

Michael Chapple, a professor of information technology at the University of Notre Dame, called Cloudflare "part of the invisible plumbing that powers many websites."

"When you access a website protected by Cloudflare, your computer doesn't connect directly to that site," he said in emailed comments. "Instead, it connects to the nearest Cloudflare server, which might be very close to your home. That protects the website from a flood of traffic, and it provides you with a faster response."

In most cases, that's a "win-win" situation, he added, but since Cloudflare helps power about a fifth of the internet's sites, it has the potential to take them down as well when its systems fail.

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Users on Downdetector reported issues on Tuesday with various services like X and OpenAI's ChatGPT. OpenAI noted on its own status page that ChatGPT was down for some users, and a spokesperson later confirmed that Cloudflare was the source of the disruption.

"Cloudflare has resolved the issue, and our services are fully back online," the spokesperson said Tuesday afternoon.

Creative-software company Canva directly mentioned Cloudflare issues in disclosing why its service wasn't loading for some users, but its latest update noted also noted that a fix was in place.

Shares of Cloudflare fell about 3% on Tuesday alongside a broader market selloff.

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The outage highlighted how online services rely on behind-the-scenes services that aren't household names to consumers - until things go awry.

"When a single upstream provider experiences issues, the impact doesn't stay contained; it cascades across industries, touching everything from social-media platforms to e-commerce checkouts and backend payment services," Fadl Mantash, the chief information security officer at Tribe Payments, said in emailed comments.

Cloudflare sells cybersecurity offerings that help sites build applications and protect themselves against threats. The company operates a network that allows it to transfer data quickly and securely in the cloud era, especially for customers looking to route information among different locations. Cloudflare distributes internet traffic throughout its network to optimize performance.

In its latest annual report, Cloudflare noted that the rise of cloud-based services has made it so that companies need more modern solutions than on-premise hardware boxes if they want to scale globally.

The company's cloud services make customers "more secure, enhancing the performance of their business-critical applications, and eliminating the cost and complexity of managing individual network hardware," according to Cloudflare's filing. Cloudflare also partners with internet service providers.

While Cloudflare may not have much name recognition among ordinary internet users, its role in transmitting and securing data has helped the company achieve a nearly $70 billion market capitalization.

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-Emily Bary

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