A collaboration between multiple Content Delivery Network (CDN) providers, including Cloudflare, has led to a new mechanism for loop protection against malicious or accidental request loops that can consume resources and degrade user's internet performance. The CDN-Loop header sets out a syntax that allows individual CDNs to mark requests as having been processed by their edge, providing a unified solution to the loop protection problem across different CDN providers. Cloudflare has recently added support for the CDN-Loop header to replace previous headers used for establishing loop protection.