An introduction to Content Delivery Networks

Being able to provide users with an ever-increasing amount and quality of content in an ever-decreasing amount of time is the driving force behind every successful business in today’s digital landscape. And, with the widespread availability of broadband internet around the globe, customers’ expectations of how they access and consume content is rapidly changing. Streaming media is much more than a luxury in today’s digital climate: in some cases, it’s a business imperative.

To cater to the global demand for media-rich browsing and other content-heavy activities around the clock, many content providers are seeking the help of Content Distribution Networks (CDNs). So, with that in mind, what exactly is a Content Distribution Network, how does it work, and should you be considering using one?

What is a Content Distribution Network, and how does it work?

A Content Distribution Network (Also sometimes referred to as a Content Delivery Network) is a network of distributed servers, deployed in multiple data centres, that deliver content to end-users based on their physical location. When the end-user accesses a website, a request for the necessary content is sent to the receiving server. This request is then redirected to the server geographically closest to the end-user, from which the required content is delivered. Should the requested content not be available on the closest server, it will be transferred from the originating site and stored as a cached copy, which will then be available for subsequent requests from the same area.

Essentially, this makes it possible for content-heavy web services to deliver content equally efficiently to users around the world. In other words, Content Distribution Networks make it possible for users to access web content from the other end of the globe without any impact on retrieval time or delivery speed.

What are the benefits of a Content Delivery Network?

The most significant benefits of a Content Delivery Network is the dramatic improvement to user experience. Traditionally, when a user accessed a web page, they would request the necessary content from the originating server, which would then be sent through multiple servers before arriving at the user’s browser. If, for example, somebody in Cape Town was requesting content from a server in Oslo, this would mean that the end-user would likely experience a significant amount of packet loss and latency before receiving the information. By storing commonly requested content locally, Content Distribution Networks reduce bandwidth requirements and server loads while delivering content to the end-user faster. In short, Content Distribution Networks bring the edge of the network closer to the end-user, resulting in faster resolution times and an optimised user experience.

What are the risks associated with Content Delivery Networks?

While Content Delivery Networks have many benefits, especially for organisations offering on-demand streaming media sites and other high-bandwidth internet services, they aren’t entirely without their risks. One of the major downsides of Content Delivery Networks is that they are typically charged for by the amount of data used. For websites with heavy traffic, this can quickly become expensive, and can have disastrous consequences for small sites that may experience periodic spikes in traffic at certain times. However, the extra cost is often more than justified by the improvement in service levels that end-users will enjoy. In the case of an unchecked Denial of Service (DoS) attack, though, the financial and infrastructural consequences can be dire. Another common criticism of Content Distribution Networks is one that is used in any argument against IT outsourcing: handing over content management to a third party takes it out of your company’s hands, meaning you no longer have a say in the quality of service. Additionally, if an outage should prevent access to the Content Distribution Network, end-users will hold you responsible and not them, which could cause damage to your company image.

Source: Iris