If you are working with websites you probably already know what a CDN is. But if you have just launched your first webserver on a virtual server or a bare-metal server maybe this is something new for you.
CDN stands for Content delivery network. In its most basic form, you describe it as a service where an operator has installed an HTTP server on several locations with high bandwidth capacity. Customers can then use these servers for offloading their web traffic against these servers. The benefit of doing so is that you get a faster website and if you don’t need to worry about the bandwidth problem that can occur if you get a high amount of traffic.
So how does it work? well, it very simple actually. The CDN server fetches content on a request and caches the files for a certain amount of time. When the next request is done, the content will be cached on the CDN and the file will be served from the CDN servers instead.
Nowadays CDN service is more advance and offers more services than just web-cache. Today you can get SSL offload, firewall, DDoS protection, and many other things.
It has also started to develop a few different specific CDN types for different end goals. The four most common are for the web, streaming, gaming, and betting.
What sets them apart is how they handle requests, how they cache files, and a few different optimizations.
If you are a happy amateur, it does not matter which one you use.
To have any type of CDN service is better than no one at all.
So why should you have a CDN service besides you can save a lot of money on bandwidths?
Accessibility, with a CDN you can achieve maximum accessibility on your website. If the truth is to be told, then no one can offer high availability with only one web server, you have to have servers around the world to be able to achieve high accessibility. Which would be very expensive to set up yourself.
Why can’t you have high availability on a server? It depends on the nature of the internet, the internet consists of thousands of operators and some really big operators. Regardless of size, any operator has problems once a year. With CDN you protect yourself against these problems.
Another important reason to have CDN is DDoS protection. More and more websites are being subjected to congestion attacks for various reasons. There may be political reasons, but most often it is about extortion.
With a CDN you get better protection against these, you can then not guarantee that you will not be affected. But your odds of getting rid of them will increase.