What Performance Problem Does A CDN Solve?

CDN refers to content delivery network. With content delivery network, the main problem, which is addressed, is latency. Latency refers to time taken by the host server to get process and finally deliver any request for a specific page resource. Besides this, CDN solves other supplementary problems like augmenting international availability and lessening the bandwidth. Latency varies with the service providers. It is as per the distance user is from server. It is further compounded by number of resources any web page encompasses.

For instance, in case all resources are hosted in London, and the user visits your page in San Francisco, then whatever request you make takes a round trip from SF to London and then back to San Francisco. If at all, your web page has less than 100 objects, which is not too many, then the browser will make 100 individual requests to the server to get back to the given objects.

On an average, latency is 75-140ms range; nevertheless, it can higher than this level, particularly for the mobile users who access a website via the 3G network. This will add up to 2 or 3 seconds of the load time, this is quite a bit in case that it is just one of the factors, which will slow down loading of the page.