In its incident report, Cloudflare says a critical issue was observed and connectivity in its network was disrupted in broad regions. "Eyeballs attempting to reach Cloudflare sites in impacted regions will observe 500 (internal server) error (s). The incident impacts all data plane services in our network," says the popular content delivery network provider.

Cloudflare said it is investigating widespread issues with our services and or network. "Users may experience errors or timeouts reaching Cloudflare's network or services. We will update the status page to clarify the scope of impact as we continue the investigation," says Cloudflare, while confirming later that the issue has been resolved.

Meanwhile, users of these online trading apps were a harried lot. "Not sure what just happened but @zerodhaonline is frozen on both pc and phone (sic)," said Twitter user @BandiShreyas.

Another user (@DhingraSaheb) tweeted: "Stockbrokers realised that market is not coming down, so they themselves went down. Some websites that are operating on Cloudflare are down. Global outrage? (sic)".

Other platforms that were affected included crypto exchange Coinbase, gaming platform Steam, communication service Discord, virtual private network service NordVPN, video conference platform Skype, ed-tech platform Udemy, and more.

What is a CDN?

A content delivery network or CDN refers to a geographically distributed group of servers, which work together to provide fast delivery of internet content.

A CDN allows for the quick transfer of assets needed for loading internet content, including HTML pages, javascript files, stylesheets, images, and videos. Since they dramatically reduce the data transfer time from the server to the website, most popular sites rely on them. Today, a majority of web traffic is served through CDNs, including traffic from popular sites like Facebook, Netflix, and Amazon. As visitors are more inclined to click away from a slow-loading site, a CDN can reduce bounce rates and increase the amount of time that people spend on the site. In other words, a faster website means more visitors will stay and stick around longer.

A properly configured CDN can also help protect websites against some common malicious attacks, such as distributed denial of service (DDOS) attacks.

Connectivity issue on upstox

Zerodha, Upstox services hit by Cloudflare outage