CDN (Content delivery networks): A Guide for Beginners

Content Delivery Networks

Content delivery networks aka CDNs are a part and parcel of modern websites and applications. Whether you know it or not, the content you view on your smartphones or PCs-videos, text, or images-are most likely delivered through a CDN.

In this brief guide on CDN, we will try to understand what a CDN Content delivery network is, how it works, how it helps your website, and how you can choose a CDN provider for your business. So, let’s begin without ado.

What is a CDN?

A content delivery network (CDN) is a globally distributed network of web servers (Points of Presence) that offer high-availability and fast performance to websites distributing their content through it. The content is replicated and stored throughout the network, and users can access the content present at a server geographically closest to them.

This method of storing content is far more efficient than the traditional one of storing content on just one central server. Instead of all the users accessing (and burdening) the central server, each user accesses the copy of the data close to him.

How does a CDN work?

To understand how content delivery networks works, let’s first understand what a CDN comprises. Every CDN has certain Points of Presence (PoPs) i.e. strategically located data centers required for communicating with users geographically close to them. PoPs bring the content closer to the user (web visitor).

Every PoP, in turn, has certain caching servers. These are web servers that store and deliver cached content to nearby users. Thanks to these servers, the page loading time of websites is considerably reduced.

Each caching server in a Content delivery network has multiple storage drives (SSD and HDD) and high amounts of RAM. RAM, being the fastest of the three, typically stores the most frequently accessed items. This way, someone sitting in the USA can access your website hosted in India through a local USA PoP. This is quicker than the user request (and your response) traveling all the way to your server based in India.

While a CDN accelerates your page-loading speed, you may not need it if the majority of your users are based in the same location as your hosting. That said, most of the websites on the internet operate on a large scale, making CDN a popular choice in most of the industry verticals, particularly media, entertainment, advertising, e-commerce, gaming, and higher education.

How does a CDN benefit your business?

A CDN network offers the following benefits to your business:

  • Performance: Because a CDN reduces the distance between the user and the server delivering content, it helps improve the page loading speed of the website. And a high page loading speed results in an enhanced user experience, which in turn leads to better ranking in search engines and higher conversion rates.
  • Availability: Availability measures how long your website remains accessible to users in a given period of time. When you deliver content without a CDN, you need to add more servers as the traffic goes up. When a cloud Content delivery network comes into the picture, a lot of traffic gets deviated to the edge server of the CDN. When the content is available on the cache, the CDN keeps serving the content, even when your servers go offline for some reason, improving the availability of your website.
  • Security: Because a CDN PoP is the first layer in the network that accepts incoming traffic, it is also the first line of defense against an attack on your website. A CDN can stop all the malicious requests coming to your site, securing it against cyberattacks. Large companies deploy a range of advanced features such as web application firewall, bot protection as add-ons on their CDNs.

How can you choose a CDN service provider?

Now that we’ve understood how a Content delivery networks works, let’s see how you can choose a CDN service provider for your business. Here are the key things you need to take into account:

  1. Content-Type: Different types of content demand different CDN solutions. Photos and videos need more bandwidth than text. As the content becomes dynamic/personalized, the demand for bandwidth goes up. If most of the content on your website is static, consider vendors with a sufficient number of PoPs dedicated to your resources. For dynamic content, take into account your vendor’s end-to-end connectivity and the quality of their software stack.
  2. Location of Users: When buying CDN solutions, you need to ensure all your users have a great experience using your website no matter where they access it from. Your cloud CDN provider should have PoPs located geographically close to your end-users. If your users are spread across the globe, choose a provider with PoPs located globally.
  3. Quality of Support: While almost all service providers claim to offer round-the-clock service, you need to consider factors beyond the availability of the service. A good vendor should be able to offer dexterously managed delivery, broadcast, and security services along with proactive monitoring and support, letting you access experts in web, mobile, streaming, and security as and when required.
  4. Performance: When assessing the performance of a cloud CDN, metrics like network latency, availability, and throughput are immensely helpful. Network latency is the time needed for the data to reach its destination across the network. Throughput is the traffic a CDN handles at any point in time, and availability measures if the network is online and accessible. In order to get clarity on these metrics, conduct a trial with your prospective CDN provider, and collect performance data for a minimum of 48 hours on all three metrics.
  5. Customizability: Your CDN provider should be able to address the unique challenges of your business. Examine how flexible their Content delivery network architecture is. Seek a provider that offers micro-level control over all aspects of content handling such as caching rules, cookie handling, access control, and performance optimization.

Still have questions on CDN? Don’t fret, we are there to help. If you are looking for CDN hosting in India, let us know in the comment section. We will be glad to answer your queries.