A content delivery network (CDN) is often viewed by newcomers as a kind of panacea for performance . The loading times of the website are bad? Then give me the CDN and everything will be fine again. At least that’s the long-lived opinion when it comes to the topic. Of course that’s total nonsense.
The CDN isn’t a secret miracle cure for better performance, nor is it a salvation when a website seems buggy or unoptimized. But what exactly is a CDN good for and who needs it?
We spoke to the expert Jörg Strömsdörfer, owner of DieWebAG©, one of the most renowned online agencies in Germany.
What exactly is a CDN?
The CDN is basically a network of many servers , all over the world . CDN providers provide a broad infrastructure that can be used by customers. The special thing about it is that it is not a question of specific server locations , as is the case with a classic hoster . Rather, the CDN intelligently selects which location is used to transmit the content. If some users come from the USA, the CDN automatically prefers a US server for delivery. Visitors from Germany, on the other hand, still get a German server.The closer the server is, the better the connection and the faster the transmission.
The different servers are also optimized to deliver individual files particularly quickly and efficiently . Images, music, videos and more can therefore be downloaded extremely quickly because they are not located on the website’s main server, but on specially optimized servers that have been optimized purely for fast downloading and a corresponding connection.
A content delivery network is used to store static assets, which can then be delivered at lightning speed . In theory, almost anything can be backed up on a CDN. In practice, however, it is often only the assets and the corresponding downloads . Let’s take a closer look at why this is so.
Who Needs a CDN?
All those who either have to process enormously high numbers of visitors or offer certain downloads are well advised to use a CDN. Anyone who has ever hosted a video on their server and wanted to integrate it into their own website will have noticed that the video loads quite slowly.
This is due to the fact that hosters usually do not optimize their servers for the pure delivery of content and often even throttle such downloads so as not to put too much strain on the entire infrastructure. In short, web hosting is not designed to ensure fast downloads, but rather to be accessible in a stable manner.
There are other problems. When individuals access a file, it loads quite quickly. But if 1,000 or even 10,000 visitors suddenly ask for a file, the server collapses and the video or download no longer loads properly for anyone. With a CDN it is different.
The CDN automatically selects a nearby server and the entire infrastructure of the content delivery network is designed to be able to deliver the relevant files as quickly and directly as possible. Independent of the actual website, because that is somewhere else. So images, videos, podcasts and more are loaded directly from the CDN and this is optimized to be close to the visitors. Therefore, if the person requesting a file is in the US, the CDN will choose an American server. If she requests the file within Switzerland, she is assigned a server in Switzerland. This keeps data paths short and efficient.
So who exactly needs a CDN? Primarily those who want to self-host downloads, videos or audio files . Or anyone who notices enormously high access numbers and would like to outsource the assets to a CDN. Images, CSS files, Javascript and the like are then loaded in an optimized manner and no longer slow down page loading.
Which CDN providers are there?
KeyCDN is often recommended in Germany. Getting started with the provider is particularly easy. Akamai is known to many because it was used by Facebook, among others. However, this is more in the enterprise area, so nothing for small websites with a tight budget.
The Amazon Web Services (AWS ) also offer a corresponding CDN with the Amazon CloudFront . And then there ‘s Fastly , CDN77 , and many more.
The company Cloudflare is taking a completely different approach . This also offers a CDN in its package, but would like to act as a complete solution. So you not only save the assets here, but your entire website. At the same time, Cloudflare optimizes everything for performance and, in addition to DDoS protection, also includes a web application firewall (WAF) and much more.
There are many other providers, many specializing in certain areas. TinyPNG , for example, offers a CDN for images, which also takes care of the optimization. Also, there are wholesale CDN providers that don’t take regular websites at all.
Conclusion on the Content Delivery Network
Does a normal website need a CDN? No definitely not. Optimization doesn’t start with a CDN, it ends there. The CDN is the last step to ensure even better performance or to achieve more efficient load balancing .
Even if videos or podcasts are self-hosted, a CDN is recommended, since ordinary servers simply cannot cope with the mass of requests. What works well with low access numbers fails as soon as several visitors access the files at the same time.
International sites also benefit from a CDN. For example, if I call up Instagram, I get the images from a CDN. If I had to load all of this from a US server, the request alone would take forever.
Lets say it like this. If you need a CDN, you usually already know this because you know your way around. If you don’t know about it, you usually don’t need it. So don’t let anything fool you. Before the CDN becomes necessary, there are many other optimizations that can bring similar success. The CDN is the last choice, especially for smaller websites and blogs.