What is a CDN and why you need one?

5 min read


With the constant evolution of the digital world, websites are providing more and more media-rich content to engage users. And the world is getting faster and smaller all the time.

Your users are more and more dispersed globally yet expect your site to load faster than ever.

If it doesn’t load fast, you will be offering not only a poor user (customer) experience, but this will often hit you where it hurts too with higher bounce rates, cart abandonment, incomplete orders and fewer sales and leads.

If this wasn’t bad enough, you’ll get a sharp smack on the wrists from the search engines followed by a slide down the search rankings.

Fear not. Some very clever people developed a nifty solution over a decade ago to not only speed up your website but also add layers of security to boot.

And so was born the Content Delivery Network (CDN).

What is CDN

A CDN acts as a virtual server network. This means that you can have your website sitting on hundreds of servers around the world instead of one.

Source: cloudflare.com

A CDN is usually focused on both optimisation and security, but depending on which CDN you choose the weighting may be different.

What’s more, it doesn’t apply just to websites, it also covers APIs, SaaS and other services connected to the Internet.

Improving website performance

Performance means speed.
And let’s face it, we’ve all got the attention span of a goldfish now. We couldn’t imagine waiting for more than a second for a page to load. If it does, we’re off to a competitor without a second thought. Neil Patel says that 40% of people abandon a website that takes more than 3 seconds to load. How long does yours take?

We all keep adding more and more “sexy stuff” to our websites to engage and delight our users. We need to balance this against the page load speed. Yet, it’s not only the media-rich content which impacts the speed of your website. It is also important to factor in your hosting service.

With much of the world (and it’s kids) working from home and online for the next few months, the internet is under a higher traffic load than normal. (This is why we’re seeing streaming services like Netflix going down and reducing bandwidth and many websites taking longer to load than normal.)

Because so many companies are operating globally, for example, if your site is hosted in the UK, but someone is accessing it in Australia, it may take extra time to load, (especially if it is image or feature-heavy).

For this reason, it is useful to be able to “bounce” the traffic around between different virtual servers to keep the latency as low as possible by load balancing the servers it is going through. This is a particularly pertinent point in light of Google’s views on mobile page speed (they need to be fast!).

A service like Cloud Flare caches aspects of your site on the server closest to the end-user optimises images and even compresses files. And you can choose what caches and for how long. This reduces the number of requests to the main server, so you can potentially make the bandwidth lower.

This greatly reduces the load time and increases the reliability – hugely improving the user experience, conversions and reduces churn when compared with a slow site. All helping to contribute to the myriad of things you need to do to keep the search engines happy too.

Read more detail about how a CDN improves performance here.

You’ll still need to ensure you’re on top-quality hosting (we use Rackspace, AWS and Nimbus) to make sure the site is as stable as possible, and a CDN will take care of the rest.

Improving website security

Depending on the make-up of your site, you used to have to compromise performance for security.

With the security landscape constantly evolving, to stay one step ahead of the game we use CDNs – especially if the site is taking any form of customer data (think GDPR).

One of the aspects of a CDN is that it helps identify visitor (and bot) behaviour that isn’t accessible to conventional analytics technologies.

To use a pub as an analogy, from a security perspective, you can think of a CDN as a bouncer on the door. If anything looks dodgy, it won’t let it in.

And if something inside is misbehaving, it kicks it out pronto.

The CDN / bouncer acts as a middleman between the outside and inside world.

If you get an angry mob of 200 banging on the front door of the pub (a DDOS attack on your server), the bouncer locks the door (firewall) and lets the good folk in round the back (a virtual server somewhere else on the network). And because CDNs often have set fees, you won’t get pricing increases if you get a traffic surge to your server under an attack.

In reality, a CDN is a network of servers between the web traffic and your server.

It constantly scans and monitors your website code and database for security or malware issues. If it finds anything suspect it removes it or lets the owner (in this case the agency) know, so they can clean it up. And those clever people who came up with CDNs have programmed them to constantly learn and adapt.

So with all that time and effort, you’ve put into creating a website which is often the shop window (and cash desk) for your business, surely it is worth a small cost to add something to increase the security and performance of your beloved asset.

Who do we recommend?

Cloudflare (established 2009) is a well-established company that offers a wide range of services, including a CDN as well as security and performance optimisation features.

The biggest and most reputable provider, they have free and paid plans, with the free plan providing basic CDN functionality and the paid plans providing additional features such as advanced caching and DDoS protection.

StackPath (2015) is a newer company that was formed by the merger of several other CDN and security companies. They offer a variety of services including a CDN, DDoS protection, and WAF.

Amazon CloudFront (2008) is a CDN service provided by Amazon Web Services (AWS). It integrates with other AWS services such as S3, Elastic Load Balancing, and Route 53 DNS, and allows for easy integration with these services. It also has a pay-as-you-go pricing model, which can be more cost-effective for some users.

In summary, Cloudflare, Stackpath, and Cloudfront are three popular CDN providers that offer a variety of features and pricing options. Cloudflare is a well-established company that offers a wide range of services. Stackpath is a newer company that was formed by the merger of several other CDN and security companies. Amazon Cloudfront is a CDN service provided by Amazon Web Services (AWS) that integrates with other AWS services.

Speak with the team to improve the security and performance of your site.