CDN Featured Article

Software-defined networking (SDN) is part of a larger movement that is fundamentally changing the way networks, data centers and the cloud are architected and managed. Mobile operators, service providers and those delivering cloud-based content all benefit from the efficiencies, cost savings and flexibility inherent in architectures that utilize SDN and network functions virtualization (NFV).

But where is the intersection between SDN and CDNs?

Taking a step back, until the last few years, networks were built using a hardware-centric approach; turnkey equipment supplied by a host of traditional networking vendors. In this pre-SDN world, a hardware-centric CDN predicated on pre-provisioned caches with limited agility sufficed quite well. 

Enter SDN, and in fact an enterprise WAN parallel is the evolution from WAN acceleration and optimization to SD-WAN – according to the IDC (News - Alert), the SD-WAN market is projected to grow at an annual compound rate of 90 percent through 2020 putting a valuation of over $6 billion by that time. This is what we call a B2B topology, connecting an enterprise’s HQ to its branches. 

But what about cloud-based companies that need to offer a better experience to all users, independent of location and device?  A post-B2B architecture, more analogous to B2C.  

If we assume many of these cloud application and content providers leverage SDN over the coming years, in most cases indirectly since they’ll just leverage whatever compute and storage architecture their cloud operator provides, how do we elevate CDNs to the SDN world?   Easier said than done.

Remember that SDN, an architecture relying on both a controller and switch, is designed for a single management domain.  This could be limited to a single data center (what I call SD-LAN), or could span the globe as realized by some of the hyper-scale operators, but there is still knowledge and control as to available resources.   Limiting a SDN-CDN to a single cloud operator would not solve the problem at-hand.  Alternative, attempting fine-grained control across operators, links, compute resources, and even entire regions subject to unavailability would be too complex and might not even provide a real-time view.   However, if the basic SDN paradigm could be extended but with additional flexibility, it could work. 

Here is where cloud-based networking comes into play, a combination of a management system that maintains a view of real-time of global Internet congestion, and virtual routers placed within every major cloud operator.  And though creation of the routers is under the control of the management platform, once instantiated, they just forward packets, but at the cloud layer. 

Cloud-based networking specialists like Teridion are at the forefront of the space, providing a Global Cloud Network that may be scaled on demand and provisioned within minutes to connect cloud content providers and their end users.

Teridion was recently voted as one of the 10 SDN Startups Driving Innovation by Network Computing magazine for its impact in the CDN space. Expanding well beyond SD-WAN and traditional CDN solutions, Teridion handles dynamic content delivery over the public Internet, addressing a growing need as more users and more devices require high-speed cloud content, any time and from anywhere. Service providers using the Teridion Global Cloud Network can scale up to hundreds of thousands of end users anywhere in the world without the need for application, client or server-side changes.

These efficiencies and speeds are achieved through the wonders of SDN and NFV and are representing a sea change in the way CDN networks operate. That change couldn’t come at a better time – Research and Markets        claims 50 percent of the content consumed by the global Internet is served by CDNs today, and that number is expected to grow to 60 percent by 2020. The research firm points out that CDNs face a number of challenges in the age of the cloud, including latency issues.

The need for service providers to overcome these issues, operate more efficiently and offer a consistently high quality of service will ultimately drive the next generation of CDNs, one that handily leverages the cloud using SDN to combat latency and connectivity challenges.