May 19, 2017 by Diana Bocco

Why You Should use a CDN and How It Affects SEO

CDNs or content delivery networks are used to provide users with alternate server nodes in order to download various static resources such as images, video, and JavaScript.

Why You Should use a CDN and How It Affects SEO

The nodes or servers are spread across the world and work by only sending data using the server which is geographically closest to the user. This kind of setup allows for latency to be drastically reduced, which ensures a quicker server response and shorter download times. Although CDNs are an ideal solution for websites wishing to improve their loading speeds, this does not mean that every website actually needs one.

What exactly is a CDN?

Basically, a CDN represents a large network of servers which are geographically dispersed throughout the world. Each node, or Edge Server, pre-caches static content and structural data from a website. Once the end-user requests that website, only the server closest to him will send the data. Since data is traveling using the shortest possible distance, the time needed for the server to accept the request and start sending data is significantly reduced, resulting in faster loading times and better user-experience.

What are the benefits of using a CDN?

Despite the fact that more and more websites are either responsive or have a mobile version, the content they host is simply not optimized for mobile devices. With CDNs, your website’s content will load faster, which is particularly useful for those trying to improve their mobile website’s performance. CDNs limit the number of open web server connections using session optimization which allows for your website to remain stable even during large spikes in traffic. Lastly, CDNs routinely remove and update old content in order to provide users with the most relevant and up-to-date experience.

Do CDNs affect SEO and how?

Most web and IT support services are in favor of CDNs seeing how they improve the quality and speed of delivery of your content. Think about it this way: effective content delivery and high loading speeds are two very important factors affecting SEO. CDNs improve both of them, albeit indirectly. And there are a lot more factors you need to consider and satisfy in order to increase your website’s ranking position. Another SEO benefit stems from CDNs use of canonical headers and advanced caching algorithms in order to ensure that your website remains exactly the same across all servers and prevent duplicate content.

Do not attempt to install and configure a CDN on your site without any technical expertise and practical knowledge. You have to know exactly what increases and what decreases the loading times of your pages in order to properly implement and use CDNs to improve your website’s performance. CDN setup is far from simple and if not executed perfectly it can destroy all your previous SEO efforts and even result in your website getting demoted or worse, completely omitted from the search results.

That said, you can use both Bing’s and Google’s Webmaster Tools for an added control of your geographical target, regardless of the IP difference between your website and CDN’s servers. This ensures that both Bing and Google will target the location you intended, instead of targeting a different location based on the IP address used by the CDN. Using Google Webmaster Tools to set up and verify a CDN subdomain is very easy and so is blocking and removing of specific URLs you don’t want to be indexed. As long as you follow Google’s Webmaster guidelines, that is.

Avoiding the duplicate content issue

CDNs cache and host site resources includes images, video, CSS, and JavaScript, as they are the heaviest elements on a website. That said, hosting an entire website on a CDN can easily result in problems with duplicate content. The reason behind this is that your website has one URL before implementing CDN and another, slightly different URL, after implementation. Now you have two different URLs leading to the exact same page, which is basically duplicate content as long as Google’s algorithm is concerned. Fortunately, this can all be sorted out easily using the Rel=Canonical tags to let Google know which URL should be indexed and displayed in the results.

As you can see, CDNs have a tangible effect on SEO. Granted, CDNs have a tendency to backfire if they’re not adequately set up and completely ruin all SEO work you have put into your website. Not only that, but Google could “downrank” your website or have it completely removed from its search results. If you’re still interested in implementing CDNs with your website, be absolutely positive that you’re doing it correctly. If you don’t have the necessary skillset required for the job, the best course of action is to hire a professional service and let them do all the work for you.

[guest post by Blake Davies]

* Image source: Freepik

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