One of the main benefits of using a Content Delivery Network is that it will improve the performance of your web content; however, before considering the parameters that impact the Content Delivery Network Performance it is important to understand why speed is so important.

The Need for Speed – Why Your CDN (and your website) needs to be Fast

Having a faster website has become extremely important in current scenario because the website visitors have become increasingly impatient and want the content to be loaded immediately. There was a study done by various Internet players (including Google and Microsoft), wherein they inserted different wait times in selected users and find how that impacted their searching trends. Over a period of 4-6 weeks, they found that there was 1% reduction in queries from viewers who had a 1 second lag, and for customers with 2-second lag, the reduction was a sizable 4%, and the trend was similar.

Apart from this, studies from Shopzilla and Mozilla show that improving their website load times helped in increasing conversions and downloads by 7-12 and 15.4 percent respectively. Finally, since speed is also considered as an important signal by the Search Engines, a faster website would mean better search rankings and thus higher organic traffic from search engines.

Considering all the above points, it is critical that the Content Delivery Network you choose helps you in improving your website and download performance significantly. Again, there are many parameters that impact the performance of CDN, and the important ones are described below.

1.Number and Locations of Edge Servers (Points-of-Presence)

One of the most important aspects that decide the performance of the CDN is the number and locations of its Edge locations. The closer you have a PoP to your target regions, the better is the performance expected to be. It is also important to know which algorithm the CDN provider uses for deciding which Edge server will serve the content to the website visitors and find an optimal path for content delivery.

2.Server Capacity and Storage Speeds

While the location of the PoP servers help in getting a geographical edge, the Content Delivery Network performance is also impacted by the type of hardware used. Typically, the new state-of-the-art servers and use of high-speed SSD disks for storage can result in a much faster content delivery than a low capacity server with normal storage disks.

3.Other Optimizations (Front-End Optimization, Optimized TCP Stack etc.)

While it is not exactly traditional CDN, some of the Content Delivery Network providers have also incorporated other optimizations for improving the performance of their customer websites. Some of these innovative solutions include implementing Front-End Optimizations and optimizing their TCP stack to further optimize their Content Delivery Network performance.

4.Compression and Other Intelligent Solutions (Adaptive streaming etc.)

Finally, to improve Content Delivery Network performance, the CDN providers also reduce the overall content that needs to be delivered by allowing customers to enable server-side Gzip compression or other similar optimizations. For content streaming, the solutions typically support adaptive streaming and change the quality and protocol of streamed media based on the customers’ device and network.

Above are the main factors that impact the Content Delivery Network Performance, and to summarize a larger number of PoP locations alone doesn’t decide on if the CDN will perform the best, but there are many other things that need to be factored as well. It is important that you consider all these aspects (along with pricing models and bandwidth charges) to decide which CDN solution to opt for.

Source: http://www.bookofspeed.com/chapter1.html