What is a Content Delivery Network?

A CDN, or content delivery network, is a system that distributes static content of the website based on the geographic location of the users. That content may include webpages, pictures, videos, files, etc.

This will make your website’s content load faster globally, and is especially helpful when you have high amount of traffics all over the world.

Why you need a CDN?

When you visit a website, you are being loaded the content from that server. If you are not using CDN, you are going to put a tiny amount of stress to the server. That doesn’t really matter until you have tons of visitors, which can really bulk down your server and cause it to be very slow and unresponsive.

If you have big sites and people finding you sites loading slow, you probably going to hurt your visitors feeling and lose some business with them.

In addition to that, geographical location matter too. The further away (physically) the users requesting copies of content from a server, the more upsetting the result is.

How does it work?

Most of the CDN services have servers worldwide. What happen is CDN service provider caches the content to those servers and when the person visit your sites, it will load the content straight from the closest server.

For example, you visitor from Japan will be able to load your travel blog images straight from Tokyo, instead of the origin server from Boston. At the same time, the shorter the distance the faster the loading speed. As a result, it improved the overall performance of your site in the eyes of visitors.

So, now you have some basic understanding of the CDN, let’s dive in to the detail. You will usually get a DNS record from your CDN provider. And all you need to do is to replace the URLs of the pictures, videos and pages links within your website to the same source provided by your CDN provider. That’s how simple it is.

Most of the time, you can either upload the content manually or letting your CDN provider fetch your site’s content automatically from your server. For example, you have a background image URL as http://yourwebsite.com/image/background.png, it will later be changed into http://cdn.yourcdnprovider.com/image/background.png.

Type of CDN

There are two types of CDNs, push and pull.

Push CDN
When you push a server, it mean that you are actually pushing/uploading the entire site’s static content to the CDN server beforehand.
Pull CDN
Pull server, on the other hand, is uploading part of the content upon requesting. For example, if someone from different country has visited your page for the very first time, your CDN server will then have to pull the particular page for the rest of the visitors in the same area. And yes, the first person may experience no improvement in loading speed.

Editor recommendation

As more and more people are looking for efficient and inexpensive way of boosting up site loading time, there are a number of relatively affordable CDNs in the market. Also, many hosting providers has featured their CDNs as part of the packages now.

Bonus: If you are not interested to the paid services, you can set up your own Free CDN on your server too. We will talk about it in the future, but there are plenty of great articles out there about how to setup a CDN on your website.

If you are looking for CDN services, I personally recommend one of the best CDN service that works perfectly on me.


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