What is a CDN (Content Delivery Network)?

A Content Delivery Network (CDN) is a network of proxy servers that makes website content more quickly available to users. This is ensured by the geographical distribution of the servers, which makes it possible to provide content from the server located closest to the end user.

Building a CDN


Definition of what a CDN is

A Content Delivery Network, less commonly known as a Content Distribution Network, enables web pages to be loaded more quickly throughout the world. The CDN can do this by using multiple proxy servers at different geographical locations. These servers are used to store static website content, including CSS and JavaScript files and images.

When a user accesses the website, the request does not have to transit multiple continents in some circumstances to reach a particular server. Instead, the CDN uses the server located nearest to the user to establish the connection.

Computer Hardware


How does a CDN work?

CDN proxy servers are deployed at strategically favorable locations in order to create a high-performing network that is as fail-safe as possible. A good example of this are the globally distributed internet nodes (Internet Exchange Points – IXPs) used by Internet Service Providers (ISPs) to connect their networks with each other. The world’s largest IXP in terms of traffic is DE-CIX in Frankfurt am Main, for example. By deploying CDN proxy servers at these high-performance nodes, CDN operators can ensure the best possible performance for data transmission.

Who needs a CDN?

The use of a CDN makes sense for many websites with heavy traffic and international users. If a website is responding to requests from all over the world without using a CDN, these requests and the requested data are being delivered to their destination via a number of nodes, meaning that it will take some time to load the website. However, by using a Content Delivery Network, webmasters can minimize loading times, which has a positive effect on both the usability of the site and search engine optimization. The following companies and organizations, among others, benefit from the use of a Content Delivery Network:


Online merchants improve their conversion rate through faster loading times and better performance.


Streaming services for video and audio use CDNs for fast and reliable delivery of their digital content. The same applies to live gaming platforms.

Public Sector

Government agencies do this to protect themselves from outages and malfunctions to be able to carry out their duty to provide information even under exceptional circumstances.

Software Provider

Providers of software downloads and updates use CDNs to ensure the reliability of their services.


How can companies benefit from a CDN?

Companies benefit from the following advantages when using a Content Delivery Network:

Fail-safe performance

CDNs handle unforeseen peak loads that would completely overwhelm the origin server.

Reduced data volume

CDNs compress web content. Smaller volumes of data are sent much faster.

Bundled requests

In addition, Content Delivery Networks combine multiple objects into data packets, making delivery faster.


Copies of the data are cached as close as possible to the user. When a request is made, the CDN transfers copies of data from the cache server located geographically closest to the user.

Lower operating costs

Reducing the load on the original server via caching also helps to avoid costly traffic, lowering the bandwidth required.

Provision of web content even before the request

A CDN analyzes user behavior on the website, enabling it to predict the next click with a high degree of probability. This means that it can load the appropriate content before the click happens, improving the performance of the website even more.

Cloud in the sky


What are the disadvantages of using a CDN?

Using a Content Delivery Network does not only bring advantages; hence, the advantages must be weighed against the following drawbacks:

  • Effort and expense: Setting up and operating a Content Delivery System involves extra effort and costs for the company. Reliable service providers provide a remedy for this.

  • Giving up control: If a company only hosts data on its own server, it has full control over it. When using a CDN, it is inevitable that some degree of control is lost.

Data Center


The problem: CDN and dynamic content

News tickers and shopping carts in online shops are examples of dynamic content. Objects like these cannot be cached by proxy servers since each user receives content customized just for them. This makes dynamic content unsuitable for CDNs.

However, modern CDNs can employ workarounds here to speed up the transfer of data. They flexibly accelerate the flow of data in real time and enable optimized routing paths for transferring dynamic content.


Criteria for choosing the right CDN provider

When looking for a suitable CDN provider, companies are confronted with a wide range of services. The following criteria will help you choose the right partner:

Traffic Management

CDN providers handle global traffic management for their customers. Load balancing ensures efficient distribution of traffic. Many providers also offer an origin shield, an additional caching layer that protects the origin server from traffic spikes.


Network security

When choosing a CDN provider, it is crucial to ensure that the provider offers network security services and, for example, provides protection from distributed denial of service attacks. Secure bot management is also essential.


Geographical requirements

Not all CDN providers operate globally, so companies should ensure that the provider they choose operates in the relevant geographical areas. Particular attention must be paid to compliance with the provisions in the European General Data Protection Regulation (GDPR) for data storage. Companies offering services in China must take special requirements into account.

Subway tunnel


CDN: what you need to know

Content Delivery Networks enable the accelerated delivery of website traffic. When choosing the right CDN provider, however, expertise in IT security should also be taken into account. In addition to the high-performance delivery of web content, the reliability and stability of a company’s own web services also plays a vital role in its digital success.

To Myra High Performance CDN