From Caching to CDN: How To Decide Which Way to Go
From Caching to CDN: How To Decide Which Way to Go
For content creators and web developers who are seeking to speed up their web pages, learn more about whether CDNs or caching works for you.
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In an attempt to speed up their websites, owners are ready to take various measures. When we talk about the speed of a website, most often we mean the speed of its content loading. There are two effective methods to improve the load time — data caching and using a content delivery network (CDN).
Both methods are good in their own way and are used by a variety of web resources. Our article aims to compare them in terms of speed of data load. Our task is not to point you in the right direction, but to provide enough details so that you make an informed choice.
What Is Caching and How Does It Work?
At its core, data caching is the process of storing information from a website on a computer for a specific period of time. Usually, caching employs the part of RAM that is not used. This process starts automatically after the user loads the website page for the first time. Saving content (images, banners, videos, text, and so on) has a positive effect on the speed of its load. And this, in turn, accelerates the speed of site loading. The user no longer needs to wait until they access the source server and receive a response.
This process makes sense not only in terms of improving the user experience but also from the perspective of improving the website's rank in search engines. For example, Google ranks fast sites higher. Demand for improved caching has resulted in various widgets hitting the market. They promise to make the caching process faster and better. However, often, this only leads to slower loading.
Of course, cached content isn’t stored forever. Usually, owners of web resources set specific caching options, including how long the data should be kept. This is done to free up the RAM space for more recent data.
What Is CDN and How Does It Work?
The way you see information on a website involves several processes. It all starts with your request for data when entering the site. The request travels to the server on which the website is running. The site receives a response from the server and the information appears in front of your eyes. Fast websites ensure that this process is maintained in a second. However, the speed of content loading is affected not only by how well-optimized the site is but also by the physical distance between the user and the server. For example, if you are located in Warsaw and the website's server is in Tokyo, then the request processing may take a longer time (~ 3-4 seconds). Therefore, using CDN image hosting, you can significantly reduce this time.
At its core, CDN is a network of third-party cache servers distributed around the world. They store cached data from multiple websites. Simply put, using a CDN, the website allows its content to be stored in several places around the globe. Expanding on the case above, the request from Warsaw won't go to Tokyo and back. Instead, it will be sent to a server in Berlin, for example. The distance is reduced significantly and site loads faster (less than a second).
How to Choose Between the Two Options?
It all depends on the specifics of the resource. The choice should be guided by what audience the site is designed for. If it is aimed at meeting the particular needs of the audience from the same city or region, then CDN is not a necessity. Since the audience is not far and not large, caching will be sufficient. On the other hand, if the web resource targets a global audience, then CDN is a necessity. CDN not only caches data but also saves dynamic content that is unique to each user (local pop-ups, promotions, offers, etc.).
Besides, it is worth noting that in order for the request processing to proceed as quickly as possible, it is necessary that a CDN is in the same network as the original server. For this, you can use many CDNs around the world or cloud CDNs. The choice of CDN should be made very carefully since some providers can slow down the speed of the website. This is a rare case, but this can happen if the selected CDN server is slower than the original server. In addition, it is better to use proven paid services and avoid free CDNs. Definitely, with a paid CDN service the overall cost of your website hosting will increase. But this way, you minimize the risks of frequent cache server crashes, which is a common case with free CDNs.
In the end, we should say that high-quality websites use both methods. Caching is a required process for any web portal. While a correctly selected CDN complements this process, making content loading instant for most users with a stable Internet connection. Everything that we talked about in this article is part of the web performance optimization process. This includes other procedures, such as reducing the size of files, reducing the number of necessary requests for data to load, and more. All this, as well as caching and the use of CDNs, is designed to improve user experience, which is the ultimate task of web designers and developers.
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