CDNs are great for WordPress sites because much of the post content is static and can easily be cached and served by a CDN. With visitors receiving cached content from the closest CDN data center, origin server load decreases, allowing sites to load faster for site visitors. At the same time, serving a site from multiple data centers makes the origin server more robust. A fortuitous spike in traffic won’t take a site down as the data centers handle the increased load.
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