Why media services need a strong multi-CDN strategy

Should you consider a multi-CDN strategy? Wilfried Dudink explores

Content delivery networks (CDNs), geographically distributed networks of servers working together to deliver fast internet content delivery, provide a dependable content distribution system for many websites and applications, including webpages, video, games, downloadable objects, streamable media, and even software updates.

CDNs are extremely popular among brands and website owners who need to deliver their content fast to a global audience. Indeed, according to data from BuiltWith, over 80% of the top 10,000 websites are using a CDN, with the global market predicted to grow from $10.9 billion in 2018 to $24.9 billion by 2025.

But recently, some CDN failures have impacted the availability of a large number of websites, bringing into question performance and availability. A root cause of these issues was the fact that many of the companies who lost availability were using a single pure-play CDN (where you have a single provider using their own infrastructure). These are traditionally designed as hardware or network-based, with Point of Presences (PoPs) deployed in geographical locations and shaped around the provider’s preference. This is often based upon the most economical option which doesn’t always automatically mean the user will get the best performance.

Although single CDNs are marketed as providing speed, security and high availability, no single CDN provider could possibly guarantee the best performance everywhere in the world, 100% of the time. Incorporating a multi-CDN strategy on the other hand, which combines multiple CDN providers to increase global reach, can deliver content of the highest quality and the best user experience, irrespective of location.

The benefits of a multi-CDN strategy

There are different ways to run a multi-CDN switching platform, but the best approach is dependent on the traffic type and use case. An optimised strategy leverages performance metrics in the decision-making process by deploying a multi-CDN platform. This means that the CDN chosen is the ‘best’ performing CDN, which has received the highest score across the board. In that case, the evaluation is based on new QoE metrics based on the specific region, for the specific piece of content, and considering the ISP and device of the end-user intending to access the content.

A multi-CDN should be considered as a solution to tackle these three critical aspects: performance, reliability and cost. Specifically:

Performance: In contrast to single CDNs, multi-CDN solutions are deployed as a combination of various PoPs from different CDN providers. This solution typically offers more PoPs spanning a much larger geographical area, giving optimal performance and virtually infinite scale, all across the globe.

Reliability: The largest providers will talk up their reliability stats and the resources they have available to ensure service uptime. But, as we’ve seen on numerous occasions, there isn’t a company on earth that is immune to technology failures, security breaches or acts of god. Spreading the reliability risk as part of a multi-CDN strategy can offer site owners reassurance that the reliability of their entire network is not a risk from a single point of failure.

Cost: Configuring a multi-CDN workflow typically requires custom tooling to stitch it all together. When this is undertaken manually across several providers, errors can creep in, potentially further complicated by how the respective CDN networks set up customers, as they’re not all done in the same way. As a result, the time and hassle can quickly add up, becoming unnecessarily costly. And even once it’s deployed, there is always more tuning and changes that need to take place, which can also impact cost. A major bonus therefore of opting to use a single provider to manage services seamlessly over the connected CDNs is that this can be implemented as one solution, managed by a single vendor, removing the burden of having to manage multiple CDN providers at the same time.

Furthermore, spreading your ‘traffic’ volume over more CDNs automatically means that the flow is diluted across each individual network, and because of this perceived decrease, a vendor may in fact charge more. This issue is resolved when deploying a multi-CDN strategy via a single provider, who can aggregate the traffic and ensure better purchase power to the individual CDNs.

Data growth and media consumption are showing no signs of slowing down – according to Statista, as of July this year over 4.33 billion people were active internet users, which effectively translates into 56 percent of the world’s population! We now live in a hyper-connected world with expectations of 100% uptime, at all times. This can only be achieved with a strong multi-CDN strategy, for better user-experiences through more coverage, performance and redundancy.