Cloudflare, one of the most popular content delivery networks, experienced technical issues on Tuesday that resulted in a number of websites and services loading slowly or becoming completely inaccessible to users.

Cloudflare first acknowledged the issue at around 1:53 p.m. ET when it issued a tweet from its official Twitter account stating, "The team is aware of issues that some customers are experiencing and actively reviewing the situation." On the company's server status site, it acknowledged it was experiencing "network Performance issues" in San Jose, Calif., though users in other locations have reported experiencing the effects of the outage.

"Cloudflare is observing network performance issues in San Jose, California. We are actively working to reduce or eliminate any impact to Internet users in this region," the company wrote, with an update provided shortly after 2:00 p.m. ET that reported the company applied a fix for the problem but was continuing to monitor the issue.

Users reported attempting to visit a number of sites and receiving a "504 Gateway Time-out" error message. The error is an HTTP status code that appears when a server does not receive a timely response from another server that it was communicating with and cannot produce the web page or other requests from the user.

The error message makes sense given the service that Cloudflare provides. Instead of allowing users to connect directly to the server hosting a website—which opens the sit up to denial of service attacks, in which an attacker floods a server with traffic in order to make it inaccessible—Cloudflare sits between the user and the website and transfers information securely through its globally distributed network.

A number of websites and services reported temporary issues during the period in which Cloudflare was experiencing its "network performance issues." Services including Streamlabs, a platform for live video streaming, and Discord, a popular communications app used primarily by the gaming community, both tweeted that issues stemming from Cloudflare were causing problems for their services.

The Cloudflare outage is just the latest example of an essential part of internet infrastructure going down, resulting in widespread problems. Earlier this year, widespread internet outages struck users in the United States after internet backbone telecommunications provider Level 3 experienced server disruptions. The issues resulted in internet outages for cities including San Francisco, Los Angeles, Boston, New York, Houston, Dallas, Minneapolis and Chicago.