Many businesses over the globe now days use the CDN technology to improve an interconnection with their customers. CDNs or Content Delivery Networks are large distributed systems of servers around the world. They are deployed in data centers across the Internet to improve data delivery. Due to the CDN, the end user gets requested data faster. The mechanism of this technology can be simply described as follows. Data is stored not only on the main server, but on a number of CDN servers, too. Such servers are distributed over the globe to be closer to the end user. When user requests for some data the first time, he or she gets it from the main server. But the second time this data will be loaded from the nearest CDN server. Surely, it is just a simple explanation. In fact, CDN communications have a lot of settings. As well as their use has a lot of secrets and distinctions.
One of the most popular services, that provide CDN, is CDN CloudFront. The service was launched in 2008 year and now has a big amount of partners and customers all over the world. It integrates with other web services to get to the best result of content delivering. CloudFront now based on fifty-two POPs (Points of Presence) all over the world. Twenty of them are in North America, sixteen – in Europe. The other POPs are located mainly in Asia and Pacific. When website starts using the CloudFront, selected data immediately goes to their edge locations. This makes data geographically close to the end users and gives them much faster access to it. Surely, everything has its cost, and every extra traffic through the CDN server will return to extra fees for online business. The most significant costs can be generated by very active files or big files. That is why it is very important to correctly select data, that will go over the CDN.