The Cloudflare outage and the dependence on large digital providers

The recent widespread blackout that impacted Cloudflare caused platforms and websites worldwide to become inaccessible. This incident has highlighted the risks associated with relying heavily on a limited number of infrastructure providers. Antonio Carzaniga, a full professor and founding member of the USI Faculty of Informatics, discussed these concerns in an interview with the daily newspaper Corriere del Ticino.

The Cloudflare malfunction was apparently not caused by a sudden increase in traffic: "It seems that the root cause of the problem was a limitation or defect in a software system," commented Prof. Carzaniga. Specifically, the system responsible for managing suspicious traffic "failed to function correctly after a routine reconfiguration because the number of rules or data provided to it exceeded a certain limit." This incident demonstrates how a faulty component, or an established limitation—known or unknown—can disrupt the entire system under certain circumstances.

Cloudflare handles between 10% and 20% of all network requests, and the outage affected approximately 30 million websites. "It is part of the network infrastructure," notes Carzaniga, referring to it as "a kind of network within the network, bringing data closer to users." For this reason, when a provider of this magnitude experiences downtime, the consequences are immediate and widespread. In the medium to long term, the expert does not anticipate any lasting effects: "I do not think there will be any medium- or long-term consequences. The fault was identified and resolved within three hours." However, this does not eliminate the underlying issue: a structural dependence on a few key players. "This represents the systemic risk associated with the exclusive use of infrastructure, such as Cloudflare."

The central issue, therefore, concerns the resilience of the entire Internet architecture. "Events like this highlight the risk of relying on a single infrastructure service," says the founding member of the Faculty of Informatics. This is a complex problem to solve, as simply increasing the number of providers is not enough. Systems need to be redesigned to be redundant and more robust. "One could consider using two or more simultaneously. But this obviously costs money, and implementation is not a given," he continues. Even within a single provider, redundancy already exists, but it is not always sufficient.

The conclusion touches on the heart of distributed systems engineering: "The problem is how to design systems so that the individual components are reliable and there is redundancy between them. It is a challenge, but that is also the beauty of engineering."

The full interview with Professor Antonio Carzaniga, published by Corriere del Ticino, is available here. (Italian only)