Multi CDN
07 Jan 2020

Multi-CDN Implementation – 5 Best Practices

A Multi-CDN implementation can offer enhanced performance, improved resiliency, and greater flexibility. However, when two or more CDNs form part of your content delivery architecture, complexity, and indirect costs increase as you need to manage various moving components that create the solution. There are, however, a few best practices that you can adopt to ensure you reap the benefits of this caching approach. By following these tips, you can lower the complexity, costs, and risks involved with coordinating and aligning multiple configurations.

The Advantages of Choosing a Multi-CDN Implementation

A Content Delivery Network (CDN) typically offers its subscribers the ability to deploy a cached copy of their content to a global network of servers. However, in some circumstances, some solution providers need to utilize the services of multiple CDN platforms. The advantages of choosing this deployment strategy include higher performance, improved flexibility, and enhanced resiliency.

Over and above these benefits, a Multi-CDN approach also gives customers the ability to reach new regions or markets. For example, if your primary CDN provider does not have a presence in China, and you need to provide services to customers in that region, a Multi-CDN implementation is your optimal strategy. Technology alignment is another example where you may need to leverage a Multi-CDN architecture. If your primary CDN provider does not offer video streaming, you will need to utilize another CDN’s platform to deliver those services to your end-users.

Multi-CDN Implementation Best Practices

Multi-CDN Architectures give you the ability to offer your end-users the best possible experience. By enabling your services to choose the best possible service for any user request in real-time, you can leverage the performance and functional synergies a Multi-CDN implementation offers. However, the management of a heterogeneous service environment does increase your complexity, cost, and risk. Below are five best practices that you can follow when embarking on a Multi-CDN strategy.

Stack Your CDNs

Stacking involves creating a CDN tiered architecture by placing one CDN behind other service providers. Leveraging this configuration results in the consolidation of user requests leading to the benefit of a higher cache hit ratio. This approach does, however, have its disadvantages. It does not manage dynamic content such as live streaming effectively. As your stacked architecture involves multiple mid-tier CDN Points of Presence (POPs), the nature of the dynamic web requests will result in every POP requesting the same live stream from the origin server simultaneously.

Consistent Monitoring Parameters

Consistency is a vital element in any Multi-CDN implementation. Ensuring you have a uniform configuration, management structure, and reporting framework is crucial in controlling any heterogeneous, dispersed technology platform. Actively monitoring your CDN infrastructure ensures you can respond to any potential issues proactively. It also provides the information you need to tweak your service so that you can give your users the best experience possible. When it comes to monitoring your Multi-CDN implementation, ensuring you configure a consistent set of alerts, thresholds, and metrics will result in you getting an accurate, holistic view of your service.

Align Content-Type with Deployment Strategy

Streamlining your Multi-CDN implementation is vital. Not only does this strategy ensure you get the best possible performance from your architecture, but it also diminishes the management overhead of running a diversified technology platform. Grouping your content by type is a proven strategy that can help you achieve these efficiency goals. There are several advantages to clustering similar content types, such as your HTML, CSS, images, and JavaScript, and routing the equivalent content across the same CDN. Streamlining the process increases the efficiency of your architecture and improves the experience of your end-users. Over and above the synergies gained, managing an environment where you have segmented the various content types can help you troubleshoot any issues. Leveraging this strategy can also help you deploy specific content types strategically. As some CDNs are better at managing different content types than others, you can utilize the best CDN possible for your caching requirements.

Use Multiple DNS Providers

DNS is the foundation of all traffic routing over the Internet and is a fundamental component in any CDN architecture. Having a single authoritative DNS provider represents a single point of failure in your design. Should your DNS provider succumb to a Distributed Denial of Service (DDoS) attack, it could detrimentally impact your solution. Industry best practice dictates that you build resilience and redundancy into every component of your infrastructure architecture. Consequently, you should apply the identical principle to any service dependency leveraged by your Multi-CDN implementation. By subscribing to the services of two or more authoritative DNS providers, you mitigate the risk of a single point of failure, ensuring the availability of your online solution.

Strive for Feature Parity

When embarking on a Multi-CDN strategy selecting providers that offer similar feature sets will make the implementation of your multi-platform caching approach more straightforward and efficient. It will also increase your flexibility as you can route your content types as needed. For example, if every provider offers the same features, you do not need to sacrifice any functionality as you can leverage every part of your Multi-CDN platform as you see fit. As with any dispersed technology platform, standardization is vital. It ensures simpler management, greater efficiencies, and allows you to leverage economies of scale that result in a lower Total Cost of Ownership.

Selecting the Appropriate Strategy for your Multi-CDN Implementation is Vital

A Multi-CDN approach offers enhanced performance, improved resiliency, and greater flexibility but needs proper implementation. Selecting the incorrect set of providers and not following a few fundamental principles could result in your solution suffering due to higher costs, increased risks, and poor performance. Multi-CDN Implementations also increase the complexity of your caching strategy, so you need to perform the proper due diligence before embarking on any implementation. However, if you stack your CDNs effectively, align your content type with your deployment strategy, and strive for feature parity, you can increase the performance and efficiency of your online solution. By enforcing consistent monitoring parameters and leveraging multiple authoritative DNS providers, you can also decrease your risk and cost while reaping the benefits of this content delivery approach.