What is a Content Delivery Network (CDN)?

Online consumers are known to abandon web pages with slow load times — that means you need your website or mobile app to be fast to delight visitors. To speed up your web assets, you need a Content Delivery Network (CDN).

What is a Content Delivery Network (CDN)?

Content Delivery Network (CDN) is a collection of distributed servers located across the globe that store files accessed by website visitors. Web content transmitted with the assistance of a CDN is delivered according to users’ geographic locations, the content delivery server, and the website’s origin.

CDNs enable e-commerce websites to quickly deliver content such as images and other files, regardless of bandwidth (traffic levels) or the user’s location. Without CDNs, load times for e-commerce stores would be considerably longer for users hundreds or thousands of miles away from the host servers (such as international customers for US-based stores).

How does a CDN work?

To minimize the distance between the visitors and your website’s server, a CDN stores a cached version of its content in multiple geographical locations (a.k.a., points of presence, or PoPs). Each PoP contains several caching servers responsible for content delivery to visitors within its proximity.

In essence, CDN puts your content in many places at once, providing superior coverage to your users. For example, when someone in London accesses your US-hosted website, it is done through a local UK PoP. This is much quicker than having the visitor’s requests, and your responses, travel the full width of the Atlantic and back.

This is how a CDN works in a nutshell. Of course, as we thought we needed an entire guide to explain the inner workings of content delivery networks, the rabbit hole goes deeper.

What are the benefits of using a CDN?

Although the benefits of using a Content Delivery Network vary depending on the size and needs of an Internet property, the primary benefits for most users can be broken down into 4 different components:

• Improving website load times – By distributing content closer to website visitors by using a nearby CDN server (among other optimizations), visitors experience faster page loading times. As visitors are more inclined to click away from a slow-loading site, a CDN can reduce bounce rates and increase the amount of time that people spend on the site. In other words, a faster website means more visitors will stay and stick around longer.
• Reducing bandwidth costs – Bandwidth consumption costs for website hosting are a primary expense for websites. Through caching and other optimizations, CDNs can reduce the amount of data an origin server must provide, thus reducing hosting costs for website owners.
• Increasing content availability and redundancy – Large amounts of traffic or hardware failures can interrupt normal website function. Thanks to their distributed nature, a CDN can handle more traffic and withstand hardware failure better than many origin servers.
• Improving website security – A CDN may improve security by providing DDoS mitigation, improvements to security certificates, and other optimizations.

Why is a Content Delivery Network needed?

For over 20 years, CDNs have formed the unseen backbone of the internet — delivering online content for shopping, banking, healthcare, and other businesses quickly and at scale.

Without CDNs, with their ability to replicate and store information from origin servers and then bring digital content close to where users access the web, the internet might be slowed to a crawl.

You may not realize it, but if you’ve done almost anything online, a CDN has probably helped provide you with a fast, reliable, and consistent experience. Here’s a simple example of how content delivery networks manage traffic behind the scenes to make that happen:

A CDN balances overall traffic to give everyone accessing internet content the best web experience possible. Think about it like routing traffic in the real world. There may be one route that’s usually the fastest from point A to point B if no other cars take it — but if it starts getting congested, it’s better for everyone if the traffic gets spread out over a few different routes. That may mean that you get sent on a roadway that’s a few minutes longer (or microseconds, when scaled to internet speeds) but you don’t get stuck in the traffic jam that’s forming on the route that is typically the fastest. It may also mean that you get sent on that fastest regular route, but without getting bogged down in traffic, because other cars are being sent on longer paths. So, it’s not a matter of slowing down, it’s about load-balancing and fully using all available resources.

The fact is, without CDNs, we’d all be stuck in traffic jams a lot more often when surfing the web.

Ready to Use a CDN Service?

If your website has slow loading times, it could be crippling your SEO and UX. In turn, this can mean losing potential customers. There are many ways to speed up a website, but using a Content Delivery Network is one of the simplest and most effective options.

A CDN works by distributing copies of your site to servers around the world. When a user visits your site, they receive the page from the closest server, reducing latency and improving performance. CDNs also reduce bandwidth consumption, enhance reliability, and strengthen security.