Cloud Strategies

Carrier SDN & the Dream of Network Agility

It is no accident that the telecom industry buzz moved from cloud services delivery circa 2012 to the hype and buzz around SDN and NFV, in which we are all currently immersed. Telecom operator interest in the cloud has not gone away, but rather operators have realized that these software-driven technologies are their best means of achieving their cloud services delivery ends.

Europe's Colt Technology Services Group Ltd has long been an early adopter of new technologies -- including cloud, NFV, and SDN, and Heavy Reading analysts tend to spend time with the operator when new trends emerge. Colt Technology Director Mirko Voltolini summed up the cloud delivery problem statement for us succinctly back in a 2012 Heavy Reading interview when he observed that while IT services could be provided in seconds with cloud computing technologies, it was still taking hours, days, and weeks to deliver the network services.

In order for cloud to be shared efficiently, the communications network has to be both dynamic and flexible -- a dramatic change from the static-pipes communications model of the enterprise networking past. Thus, for Colt and other early cloud adopters, the goal became taking those cloud and virtualization tools that transformed the data center and applying them to the WAN to deliver similar benefits of speed, flexibility, and elasticity. These benefits can also be described by the umbrella term "network agility."

Significantly, as operators were identifying these network agility goals, they also saw SDN emerging as a strong potential enabler, particularly in the areas of efficient and economic scalability and enabling flexible and dynamic traffic transport, across multiple layers.

One of the means to greater network agility is through IP/optical integration, which we wrote about extensively in a previous column. (See SDN-Enabled IP and Optical Integration.)

While the concept of full physical integration of optics and routers in a single device continues to struggle (i.e., IP over DWDM), there is significant operator interest in a tight coupling of the software control and management of the IP and optical layers, with the data planes being kept in separate hardware. SDN is viewed here as a standardized, vendor-agnostic means of tying these layers together.

Another way to increase network agility is to tightly couple control across network segments or domains, so that, for example, a service can be provisioned across access and metro networks, end-to-end, without requiring manual intervention along the way. This type of functionality has long been demonstrated by vendors at trade shows, but multi-vendor interoperability (and thus some form of openness and standardization) is required for wide-scale, real-world deployments. Here again, SDN is seen as the standardized, software glue that can tie multi-vendor domains together to achieve greater network agility.

As the SDN hype continues to increase and as the SDN concept itself becomes more amorphous, it is important to keep these operator end goals in mind: to create networks that are more agile and adaptable to the cloud. In the end, there may be no single SDN protocol, standard, or architecture winner: Instead, we may see multiple approaches emerge that are used by different operators in different ways to achieve these goals.

— Sterling Perrin, Senior Analyst, Heavy Reading

@mbushong 10/27/2014 | 9:41:02 AM
Not just for transport The same ideas of extending networking domains end to end so that services can be provisioned quickly apply to the datacenter. In fact, the same technologies (DWDM in this case) can effectively create what looks like a Metro E ring in a datacenter, providing high-capacity, low-latency connectivity between resources along with the ability to create programmable cross-connects for specific users, applications, or workloads. 

The marriage of SDN and optical makes perfect sense. Applying that marriage to a lot of different places makes equal sense.

-Mike Bushong (@mbushong)

Sign In