A CDN is an essential part of any modern website. Whether we know it or not, each of us interacts with a CDN on a daily basis when browsing social media feeds, reading articles, watching Youtube videos, or shopping online. No matter what type of content you access, there is a very high chance you’ll find CDN behind every piece of text or media on the web. In this article, we will try to explain why CDNs are so important and widely used, and what issues they are made to resolve, as well as provide some useful information. Let’s jump into it!

What is a Content Delivery Network?

A content delivery network (CDN) refers to a highly-distributed network of web servers (also known as Points of Presence or PoPs) whose goal is to provide faster and better content delivery. These servers are geographically scattered and each server stores a cached or replicated version of the content so users can access the data that is stored at the location geographically closest to them. This can help users around the world view the same high-quality content without affecting their loading times.

What does CDN stand for?

C - Content

D - Delivery

N - Network

A Content Delivery Network (CDN) refers to a group of geographically distributed servers that speed up the delivery of web content by bringing it closer to where the users are. CDN can also stand for Content Distribution Network and it refers to the same thing.

How does a CDN work?

The main goal of a CDN is to reduce latency - the time between submitting a request and a page fully loading on a device, by reducing the physical distance the request has to travel. For example, a user from the US wants to view the content that originates from a centralized server in the UK. Without a CDN, the user would experience poor loading times if the request had to cross the Atlantic.

To combat this issue, CDN stores data in earlier mentioned PoPs. Essentially, CDN places your content in many places at once, providing coverage to all of your users. Not only does it shorten the distance but it also offloads the traffic sent from the original server, resulting in fewer failures as well as cost savings for the content provider.

Benefits of using a CDN

As we already mentioned, the main reason to use a CDN is to reduce latency, but that is not the only benefit. There are other use cases for a CDN, and depending on your business needs, the benefits of CDNs can be broken down into 4 major components:

Improve page loading time

By distributing content closer to website users via a nearby CDN server (as well as other optimizations), website users experience faster webpage loading times. Visitors are more prone to bounce away from a website with high loading times. In fact, 1 out of 4 customers will abandon a webpage that takes more than 4 seconds to load. High loading times are also linked to a low ranking of a website on search engines. 

Having a CDN can reduce “bounce rates” and increase the amount of quality time users spend on your website. All of this means that, when using a CDN, content providers can provide fast and quality web content to all of their users, regardless of their location, browser, or device they are accessing it from. Web pages will load quicker and users will stay more engaged.

Improve website security

Whether your business is big or small or you have your own personal website, it is important to have fast and uninterrupted service. There are many factors that can lead to slow website performance, but a significant one is a sudden spike in traffic. This can be due to legitimate reasons like content that went viral, but it can also be a result of a far more malicious action such as a DDoS attack.

If your website is a target of a DDoS attack, a lot of traffic from the attackers will be directed toward your servers. CDN ensures it does not reach the origin server and does not render your website unavailable. When a server is hit with more traffic than it can handle, it simply redirects the traffic to other servers. There will be no downtime, and your users should not notice a thing. CDN ensures your website is always online, functional, and well-performing and users associate it with reliability and professionalism.

Increase content availability

Availability means that the content remains accessible to end users at all times, especially during periods of excessive traffic when too many people are trying to access the website at the same time or when the origin servers are down (or not working properly) for whatever reason. When serving the content from your servers, you need to add more servers as the traffic increases. If there is an unexpected issue with a server or a database, it could take the entire website down.

A CDN addresses this in two ways. First, CDN serves a lot of content from its cache, so the majority of traffic doesn’t even come to your servers. Second, even if your origin servers are down, as long as the content cache is available on the CDN, it will continue serving the content. This gives you some extra time to resolve issues on your servers while the CDN serves whatever content it can from its cache.

Reduce bandwidth costs

CDNs serve cached content so that the origin server does not have to deliver the content over and over. Web hosting companies’ prices vary, according to the amount of data that is transferred from or to the origin server. This data transfer is usually called bandwidth. However, if most of the website’s content is cached through CDN servers, far less data needs to be transferred to or from the host server, which results in lower bandwidth costs.

Most CDNs charge for their services, but the savings on monthly data transfer costs usually outweigh the cost of using the CDN.

Is the CDN the same as web hosting?

While CDN does not host content and cannot replace proper web hosting, it does help cache data, which improves overall website performance. Many websites have a hard time meeting their performance needs with traditional hosting services, which is why they opt for CDNs. By using cache to reduce bandwidth, improve security, and provide uninterrupted service, CDNs are a great choice to relieve some of the major concerns that come with traditional web hosting.

Web hosting meaning

Web hosting is used to host your website on a server and let users access it over the internet. Web hosts provide the technology and resources required for the effective and secure operation of your website. The key difference between web hosting and CDN is that web hosting stores all of your content in one place, while a CDN serves to speed up the delivery of that content by using geographically scattered servers.

Which websites should use a CDN?

A CDN can use pretty much everyone. They are made to provide a faster and more reliable experience for people on the internet. Content owners use CDNs to improve customer experience, lower bounce rates, and increase conversion rates. Most websites that operate on larger scales use CDNs to maintain accessible and reliable content and keep their websites secure.

Is a CDN necessary?

It is not always a case that a website needs a content delivery network. Such cases are, for example, websites that target visitors from a specific country or location. In that case, having a geolocated web hosting might be better than a geolocated CDN. However, if you plan on growing your website and intend to attract an audience from around the globe, a CDN is a good option for you.

Publitio’s server infrastructure acts as a CDN. Publitio has servers in 6 data centers: in the US (New York and San Francisco), Europe (London and Amsterdam), and Asia (Bangalore and Singapore). Sign up and get 14 days free trial.