What is CDN?

what is cdn

CDN stands for Content Delivery Network. To be more specific, it’s a network of servers working together to improve the speed at which the internet delivers the content on your website. CDN services may also protect against DDoS attacks and certain types of malware.

How does it work?

Internet exchange points (IXPs) link competing networks and allow data to flow from one network to the next. CDN providers place their servers at IXPs in different countries. By piggybacking on the IXP network, the CDN provider reduces its costs and improves data delivery speed.

What are the results?

The CDN provider places a cache of each client’s website on the provider’s global servers. This technique reduces latency, improves reliability, protects data, and reduces bandwidth usage.

How do CDNs reduce latency?

Web-users today have little tolerance for a slow-loading website. Using a CDN makes it possible for businesses to improve their load times through multiple actions:

  • Taking advantage of the geographically diverse nature of the network to reduce the distance that information must travel to reach the user. Users will receive a cached version of a site from a data center close to them, and the resulting reduction in latency improves the customer experience.
  • Optimizing software and hardware to enable load balancing.
  • Using solid-state hard drives to enhance speed.
  • Using techniques such as file compression and minification to reduce file sizes as much as possible.
  • Enabling TLS false start so that sites using SSL or TLS certificates load faster.

How do CDNs improve a website’s reliability?

Every second that a website is offline, it’s losing money. The first half of 2020 showed an increase in DDoS attacks. In some cases, the acts were purely malicious. With others, a profit motive was clear.

There are a few ways for DDoS attacks to bring in money. People may hire bad actors to attack competitor sites. It’s also common for bad actors to attack a company and demand a ransom to stop the attack.

Many network providers monitor for anomalies in traffic routed through their services. This monitoring allows them to identify patterns that indicate there’s an attack.

It’s not just bad actors to consider. Technical issues with the website’s host might also impact how well the site displays. CDNs reduce downtime by functioning in several ways:

  • Balancing traffic across a range of servers relieves congestion on the network. This feature also allows CDNs to make allowances for sudden bursts in traffic.
  • A built-in failover feature means that if one or more servers fail, the rest automatically pick up the slack.
  • If the issue is with a data center rather than with a few servers, CDNs reroute the traffic to the nearest available center.
  • If the origin servers are offline, cached versions of the site are still available at the CDN centers. While functionality will be limited, visitors will be able to look around.

How does a CDN protect data?

A CDN secures a site with an up-to-date TLS or SSL certificate. Depending on the service you’ve chosen, the company may also provide early warning of a DDoS attack.

Many companies in the industry now use artificial intelligence to identify a potential DDoS attack. Should it be a confirmed DDoS attack, the client may request that the CDN service limit traffic from a specific location or cut it altogether.  

How might a CDN reduce bandwidth usage?

Each time a user wishes to browse a website, the browser sends a request to the origin server. This process uses bandwidth. Having a cached version at different data centers reduces the number of requests to the origin server.

What are the top 3 CDNs?


Cloudflare is one of the world’s best-loved CDNs. Cloudflare has a generous free plan and a simple interface that is easy to use. Installation is as simple as updating your website’s DNS nameservers and selecting Cloudflare. Cloudflare does the rest.

In addition, the Pro plans provide additional features such as image optimization.

Many of our recommended hosting in Australia, best hosts in Canada, and top web hosting providers for UK offer Cloudflare integration for free. Some of the top examples include names like HostPapa & Siteground.


Akamai is also a trusted provider in this industry. The company claims to manage a third of the traffic on the internet. A vast network of servers allows Akamai to offer clients a seamless service.

Setting up the service requires some technical expertise. The company provides full instructions for clients to get started.


Fastly’s advantage is how much clients may configure it. While this adds to the complexity of setup, the ability to configure the CDN is useful for webmasters who need specific solutions for different content. The company is well-established, and its service delivery is excellent.

It’s a wrap

A Content Delivery Network is an essential tool for keeping the internet running more smoothly. For a webmaster, it’s a useful, multipurpose option. Without this tool, webmasters would have to choose local hosts to get their users’ best speeds. With these networks in place, webmasters may confidently access a global pool of hosting services.

The reduction of latency, enhancement of security, and improvement in traffic speed make using a CDN a wise move.