CDN (content delivery network)
A CDN is a network of servers spread around the world that each keep a copy of your site, so a visitor's browser can load it from the nearest one instead of one far away.
A CDN, short for content delivery network, is a set of servers in data centres around the world, each one able to hold a copy of your site and hand it to a nearby visitor. Instead of every request travelling to one server in one city, it travels to whichever data centre is closest. Closer means fewer network hops, and fewer hops means a page that shows up faster.
The idea used to be an add-on. You had a server somewhere, and you paid a separate company to cache your pages in front of it so overseas visitors did not wait as long. On the sites I build, the CDN is not an add-on. It is the whole hosting setup. There is no separate server sitting behind it. The the edge network is the origin.
That distinction matters more than it sounds like it should, because it removes an entire class of problem. A server that only exists in one place is a single point of failure and a single bottleneck. A network with copies everywhere has neither.
Why it matters to you
Page speed affects how many visitors stick around, and it affects how Google ranks you. A CDN is one of the cheapest ways to buy speed, because you are not paying for more computing power, you are paying for geography. Your customer in Kamloops and a stray visitor in Frankfurt both get a fast page, from different servers, without you doing anything extra.
It also matters for resilience. If one data centre in the network has a bad day, traffic shifts to another one automatically. A single rented server does not have that option. When it goes down, your site goes down with it.
How I set it up
I do not add a CDN as a layer on top of a rented server. I build the site as a static site, files ready to serve, and deploy it directly onto the CDN’s own network. That means there is nothing separate to configure, nothing to keep in sync, and nothing extra to pay for as traffic grows. The cache rules that decide how long a page can sit at the edge before checking for a new version are set once, as part of the build, not managed by hand.
What it looks like in practice
You will not see the CDN directly. What you will see is a site that loads quickly no matter where the visitor is standing, and a bill that does not go up when a page suddenly gets shared and a few thousand extra people show up at once. That is what the network is for. It absorbs the spike, because the spike is spread across hundreds of data centres instead of landing on one machine.
Questions I get about this
- Isn't a CDN just for huge sites with millions of visitors?
- No. That used to be true when a CDN was an extra service you bolted onto a server. Now it is often the hosting itself. A small local business site gets the same global network as a large one, at no extra cost and no extra setup.
- Does a CDN replace my web host?
- For the sites I build, yes. There is no separate rented server behind it. The CDN's own servers are the host. Older setups sometimes use a CDN in front of a traditional server, which still helps but is a different arrangement.
- Will a CDN make my site faster even for local customers?
- Yes, and often noticeably. Even a customer two streets away from your old server benefits, because the copy of your site nearest to them loads without waiting on distance or a single machine handling every visitor at once.
Want this set up properly for your business?
This is the kind of thing I build every week. Grab a time and we will talk through what fits.