Yesterday, the World experienced one of the largest Internet outages affecting social media, international media, and other high-traffic platforms. The websites that were massively impacted were Amazon, Reddit, BBC, New York Times, Guardian, Financial Times, Twitch, Spotify, Reddit, Stack Overflow, GitHub, gov.uk, Hulu, HBO Max, Quora, PayPal, Vimeo, Shopify, Quora in India, amongst others.

This problem arises from San Francisco’s cloud services provider Fastly’s content delivery network (CDN) which helps companies load their websites faster. An hour and a half into the outage, Fastly announced that it was investigating into the CDN service shortly after which they identified the issue and attempted to fix it. Fastly stated, “The issue has been identified and a fix has been applied. Customers may experience increased origin load as global services return.” On Twitter, the company said that a service configuration had triggered the disruptions, and had been disabled.

After the outage was fixed, most of the online platforms were back on track and were processing traffic smoothly. However the outage has surfaced many questions about the workings of the Internet with many asking, what exactly is CDN.

Imagine you set up a website on the internet and soon end up receiving high traffic on it. Many viewers, all around the world, are reading your content on the platform. However, the rate at which they can open articles on the website varies from country to country. and city to city. People living in your area will have no issues accessing the said articles immediately, but people living further away from you or in a different country altogether will have to wait for a couple of seconds for an article to load properly thus experiencing slow content delivery than those within your own city. This in turn ends up creating inconsistency in user experience. CDN fixes this issue and ensures that everyone has a similar user experience.

Thus, CDNs assist in boosting cache performance so that web pages may be loaded faster than feasible by cache data since the original server does not have to be retrieved. Hence, when a CDN provider like Fastly ceases to perform, it subjects all the companies using Fastly to traffic spikes and malicious attacks such as Distributed Denial of Service (DDOS) attacks.