What is Multi-CDN? If you work in video streaming, chances are you have come across this term at industry events or in trade publications. And there are many good reasons behind the hype.
In a time of fierce competition between streaming services and demanding consumers who expect nothing short of the best streaming experience, Multi-CDN or relying on multiple CDNs to distribute your content to your end users is quickly emerging as a winning strategy for industry players of all sizes.
In this blog, we explore what exactly Multi-CDN is and why it is key for streaming businesses to adopt this approach to content delivery if they want to deliver a superior user experience and optimize infrastructure costs.
What is a CDN or Content Delivery Network?
First things first: what is a CDN? A CDN or Content Delivery Network is a geographically distributed network of servers used to host media content such as videos, images, or web code. Instead of depending on a single central server to deliver your service’s content to your users regardless of their location, using a CDN allows you to host your content closer to where your users are.
When a user requests a specific piece of content, the request is sent directly to the CDN, which re-routes it to the closest server within the network. This process enables users to access content in near-real time, reducing latency and video playback issues like buffering or drops in video quality. That is why most streaming services today rely on a CDN to distribute their content more effectively.
What is Multi-CDN or M-CDN?
As the name suggests, Multi-CDN or M-CDN refers to the increasingly popular practice among online video providers of using more than one CDN at the same time. By investing in a Multi-CDN architecture or Multi-CDN portfolio, content providers can easily scale their reach to other geographic regions or have more than one option from which to choose within a given region.
With a M-CDN strategy in place, streaming services can assign each request to one CDN or the other based on their specific business and audience requirements. Let’s say, for example, that you exceeded your traffic quota for a given CDN in a specific region. With an M-CDN strategy in place, you can then choose to send all further content requests to another CDN in the region. This shift from one CDN to another is known as Multi-CDN switching or Multi-CDN load balancing, and it has many advantages if done in a systematic and strategic manner.
The benefits of adopting a Multi-CDN strategy
The benefits of adopting a Multi-CDN strategy range from ensuring greater redundancy to having more control over your content distribution costs. Having a robust Multi-CDN architecture allows video content providers to:
- Avoid outages and reduce customer churn: like any other network, CDNs are prone to crashing. By having more than one CDN, providers can avoid service outages whenever a CDN fails and prevent the loss of customers associated with these episodes
- Eliminate traffic bottlenecks: with multiple CDNs per region, you can redirect traffic to a less crowded CDN whenever there is an increase in concurrent users on one CDN
- Scale up geographically: providers can choose the best CDN for each reason where they operate, building an overlapping global network of CDNs that optimizes content delivery for a truly global and consistent streaming experience
- Tailor content distribution to your needs: a Multi-CDN portfolio gives you the flexibility to adapt content distribution to the specific needs of your business and audience. You get to pick the best CDN at all times best on your requirements of choice
To learn more about the benefits of M-CDN, read our in-depth article on the key reasons to implement a Multi-CDN strategy.
How Multi-CDN switching for video streaming works
That is all well and good, but how exactly is the switching between CDNs done? Multi-CDN switching is a complex process involving a load balancing algorithm that analyzes CDN performance and assigns each request to one CDN or the other based on a series of predefined rules.
A representation of how Multi-CDN switching for video streaming works
The most advanced Multi-CDN switching systems, like NPAW’s CDN Balancer, can automatically make this switch for each chunk of video — not only each request — and based on real-time end-user performance data.
Read our article on how to implement smart Multi-CDN switching for a closer look at what is needed to adopt a smart M-CDN strategy.