What Is a Content Delivery Network (CDN)?

Blog 7 min read | Oct 27, 2022 | JW Player



Content delivery networks (CDN) do just as the name suggests—they deliver cached internet content from local server locations to accelerate sending. The farther a visitor is from where your site is hosted, the longer it takes for the data to reach them.

Every second counts. 

Sites with a 1-second load time have a conversion rate 3x higher than a site that loads in 5 seconds and 5x higher than a site that takes 10 seconds. You could increase your conversion rate by about 5% by just making your site load 1 second faster. Can you think of any growth hacking, marketing, or sales tactic that can boast the same return on investment?

CDN services aren’t new. They were first built in the 90s out of a need to maintain internet speed and high performance. At first, they could only handle static content such as audio files, video, and software downloads. Today, they’ve become more sophisticated and complex. They can store and deliver dynamic content, such as personalized experiences and live streams.

Below, we’ll take a look under the hood and explore what a CDN is, how it works, who needs one, and how you can get started with a CDN.

What Is a Content Delivery Network (CDN)?

A content delivery network (CDN) is a distributed network of servers designed to deliver content quickly to your visitors. By placing servers in strategic geographic locations, a CDN closes the gap between content and consumers, leading to the following:

  • Faster content transfers
  • Enhanced website performance
  • Reduced hosting bandwidth
  • Improved security
  • Fewer service disruptions
  • Limitless scalability

Think of a CDN as a distribution center. When you purchase a product from an ecommerce store, you could receive your item the next day or in a week—it all depends on the location of their nearest warehouse. 

The same goes for a CDN. When a visitor opens your website or application, it might load in 1 second or 5 seconds—it all depends on the location of the nearest network server.

What’s a Multi-CDN?

A multi-CDN is a combination of several CDNs under one extensive global network. They’re a more sophisticated solution that expands your server access, accelerates transfer speed, and provides you with a backup plan in case a single CDN network experiences downtime.

Multi-CDNs make intelligent routing decisions based on location, performance, reliability, and cost in real time. This empowers them to selectively send traffic over the CDN that’s the best fit based on your customer’s characteristics.

Most CDNs don’t have network points of presence (POPs) or third-party data center connections in every country, which means organizations must use several CDNs if they want a broader international presence. However, it’s simpler to work with a single multi-CDN rather than trying to piece together several one-off CDNs to meet your web content delivery needs.

Since multi-CDNs benefit from economies of scale, they’re typically not that much more expensive than a single CDN. And the improved reliability, uptime, and customer experience make them well worth the price. Remember what a single second can do for your bottom line?

How Does a CDN Work?

CDN providers work by placing servers where internet service providers (ISP) connect at locations known as internet exchange points (IXPs). This allows the ISPs to pull data from the nearby CDN server rather than the site or application’s origin server. Shorter travel times lead to quicker service.

Despite the similarities, a CDN doesn’t act as a traditional web host—you’ll still need a web hosting provider for your website or application. Instead, CDNs cache content at the network edge, making it faster for servers to retrieve and deliver the necessary data.

Beyond speed, CDNs work to improve your uptime and enhance security, helping your site survive malicious attacks, connection errors, and standard internet congestion. If there was a power outage or internet attack on your origin server, customers could still access the website content cached on your CDN edge servers. CDNs also use minification and compression to reduce file size, meaning smaller transfer sizes and faster page load times.

Top Benefits of a CDN

We’ve mentioned a few of the advantages of a CDN throughout this piece, but here’s a more condensed list of all the benefits:

Quicker Load Times

Nearby CDN servers reduce the physical distance, leading to faster load times and reduced bounce rates and latency. More people reaching your site (and staying there) means improved conversion rates and a better bottom line for your business.

Reduced Bandwidth Costs

CDNs reduce file sizes with minification and file compression. Smaller files lead to less bandwidth consumption. Additionally, visitors use bandwidth whenever they ping your origin server with a user request. Cached content in your CDN servers means fewer pings for your host server, and that means lower costs for you.

Enhanced Website Security

CDNs offer services like bot TLS/SSL certification, distributed denial-of-service (DDoS) protection, bot mitigation, and web application firewalls (WAFs) to protect you and your customers’ information.

Improved Availability and Uptime

Network failure, web traffic spikes, and power outages can crash a web server and stop users from accessing your content. CDNs intelligently redistribute content when a server goes down, ensuring your customers never skip a beat when browsing your application or consuming content.  

Optimized Performance

CDNs use load balancing and solid-state hard drives to efficiently optimize traffic during high traffic spikes. You can see how this would be a game-changer during busy shopping holidays like Cyber Monday or for a network video streaming the Super Bowl to 100 million distributed fans.

Which Organizations Need a CDN (Use Cases and Examples)

We believe that any organization with a website, mobile application, or content repository needs a CDN. However, they’re essential for the following:

  • Websites: Even something as simple as a blog could benefit from a CDN, especially if it has high traffic or large fluctuations.
  • Mobile Applications: Users expect mobile applications to perform quickly. CDNs can deliver dynamic location-based content to users, meaning everyone gets personalized content and experiences quickly.
  • Broadcasters: CDNs help your live streaming content reach your end-users as close as possible to real-time. They also reduce buffer times and redistribute traffic during spikes.
  • Film and TV: Users can better stream live and on-demand content when it’s served by a CDN. The video content will load faster, and users (regardless of where they are) won’t have to watch the loading circle keep spinning.
  • Online Course Platforms: Most online courses rely heavily on video content. This is better served to consumers by nearby CDN servers, especially for high-trafficked courses with many users simultaneously taking the class.
  • Fitness Classes: You don’t want your stream to start lagging when your students are stuck in down dog. CDNs keep the user experience streamlined and immersive, as well as expand your potential audience base.
  • SaaS Companies: A CDN can help balance web requests when your API gets called millions or billions of times per day. 
  • Ecommerce: You can’t afford for your online store to crash during Black Friday or holiday sales. Ensure every customer can watch your product videos, browse images, and complete checkout—even when the traffic reaches new all-time highs.

Choose a Video Platform You Can Trust

When video is at the heart of what you do, you can’t settle for less. Use a complete video platform you can trust to host, deliver, and monetize your content.

JW Player provides you with a multi-CDN solution with network POPs in 130+ countries. That means you can deliver buffer-free content to practically any region in the world with 99.99% global uptime. Our platform transcodes your content for all screens, devices, and bandwidths, which means every viewer gets top-notch efficiency and high-quality content.

Whether you want to host live streams or video on-demand, we’ve got you covered. Go live in less than 30 seconds, and get your recorded replay published less than one minute after your stream finishes. Stream to your web player, OTT app, or social media platform with our third-party integrations, APIs, and SDKs.

Protect your video content with industry-leading security and digital rights management (DRM). Our DRM solution works with other video platforms, players, and CDNs to ensure you maintain complete flexibility, control, and ownership.

See for yourself. Start your 30-day free trial to experience first-hand how our multi-CDN approach can transform the way you deliver video content.