Content Delivery Networks (CDNs) are a traditional mechanism for both improving the delivery speed of a web site while also reducing the network load on the origin servers that provide the web site. The CDN accomplishes these two goals by offloading static content from the origin web servers into edge servers that are distributed around the Internet close to the users accessing the web site.
When a user on the Internet accesses a web site backed by a CDN, the dynamic content requests are typically serviced by the origin web servers while the static content requests are serviced by the CDN. Large CDNs are typically comprised of hundreds to thousands of edge servers globally distributed to be close to all of the Internet’s users – making them ideal places to store web site content for fast retrieval by web site visitors.