jsDelivr's answer:
jsDelivr is the only free CDN that aims to be production ready even for the most critical workloads. It has multiple failover systems for all of its components to ensure 100% uptime and uses multiple CDNs and datacenters for better performance.
Based on our record, CoralCDN seems to be more popular. It has been mentiond 2 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Despite a bunch of Googling, I can't figure out what ever happened to it. There's no Wikipedia article on it for some reason. The CoralCDN web site has been down since some time in 2020, judging from the Wayback Machine. The most recent cached version says nothing about an impending shutdown or any problems. Source: about 2 years ago
📎18. coralcdn.org: If a site is down due to heavy traffic, try accessing it through coral CDN. Source: about 2 years ago
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