Understanding CDN: Definition, operation and usefulness in SEO

by our Web Agency and our SEO Agency Optimize 360

The Content Delivery Networksmore commonly known as CDNare now essential when it comes to improving the performance and security of a website.

In this article, our Web Agency Optimize 360 takes a look at the concept of CDN and how it can have a positive impact on your natural referencing.

Definition of CDN: What is a Content Delivery Network?

A Content Delivery Network (or content delivery network) is a set of servers distributed geographically in several datacentres around the world.

The main purpose of a CDN is to distribute static resources (such as images, videos, files, etc.) over the Internet. CSS or JavaScriptetc.) of a website to Internet users quickly and efficiently.

The principle is based on the use of several points of presence (PoPs) located as close as possible to end users to reduce latency and optimise web page loading times.

How does a CDN work?

Geographical distribution of servers

A CDN works by caching and serving website resources from servers located geographically close to Internet users.

So when they make a request to access one of your web pages, they are automatically redirected to the nearest CDN server, rather than connecting directly to your origin server.

Data caching and synchronisation

To serve a website's resources efficiently, the CDN caches and stores the files concerned on its various servers.

It then regularly synchronises this data with the origin server to ensure that end users are provided with an up-to-date version of the content.

If a file is modified on your origin server, the CDN is generally informed automatically in order to update its cached copy.

The benefits of CDN for SEO: Why is it important?

Although the use of a CDN is not directly linked to SEO, it can have a considerable impact on several key factors that influence the position of your pages in search engine results. Here are some of the benefits of using a CDN in relation to your SEO:

Page display speed : Thanks to the geographical distribution of servers, a CDN speeds up the loading time of the resources on your pages.
However, the loading speed is a criterion used by Google to rank search results. The faster your site, the better your rankings in the SERPs (Search Engine Results Pages).
Site security and reliability : By not relying solely on your own server to distribute your content, you can avoid performance problems if your server encounters difficulties (overload, breakdowns, etc.).
What's more, many CDNs offer additional features to enhance the security of your site, such as DDoS protection or the use of SSL certificates.
User experience optimized : Improving the display speed and availability of your site means a smoother, more enjoyable user experience.
Visitor satisfaction is also an indirect criterion taken into account by Google when ranking your pages.

What are the main CDN platforms?

There are now a large number of CDN providers, each offering specific performance, prices and features. Here are a few examples of companies specialising in CDN services:

Cloudflare
Akamai
Amazon CloudFront
Fastly
MaxCDN
Incapsula

Before choosing a service provider, you need to assess your requirements in terms of traffic volume, the geographical distribution of your users and the security options required.

How do I configure a CDN for my website?

Setting up a CDN on your website can be fairly straightforward, depending on the solution you choose and the technologies used to create your site. Here is a general method for configuring a CDN:

Register with a CDN provider and choose the package best suited to your needs.
Create a new account (or configure an existing domain) with the required parameters, such as the address of the origin server, the geographical zone, etc.
Get the domain name provided by the CDN or define your own sub-domain (for example, cdn.example.com).
Configure your website so that it uses this new domain (or sub-domain) for static resources, modifying your links and tags if necessary. HTML.
Test your site to make sure that the files are being served by the CDN without any malfunctions or errors.

Some CDN solutions also include specific plugins or extensions to facilitate their integration with the main content management systems (CMS), such that WordPress, Joomla or Drupal. These tools generally enable rapid, automated implementation.

Going further with CDN and SEO

Ultimately, using a CDN brings significant advantages in terms of performance and security for your website.

Gains in display speed and user experience can play an important role in improving your natural referencing.

Don't hesitate to explore the different options available, and to devote time and resources to setting up a CDN solution tailored to your needs.