Network Infrastructure

OpenFlow SDN Solutions Increase Operator Flexibility

By TMCnet Special Guest
Mitch Auster, Senior Director of Market Development, Ciena
  |  September 03, 2013

Operators are living in challenging times. They have entered an era where double-digit traffic growth is outpacing cost reductions. Operators are also facing increasing competitive pressure that has reduced their traditional wireline revenues and profitability. And to top it all off, they are dealing with the threat of over-the-top services capturing a larger wallet share while they foot the bill. Ultimately, operators need a new way to monetize their network assets – and they need it now.

Software-defined networking and OpenFlow can help them achieve this. How? SDN with OpenFlow provides the framework and tools to enable symbiotic linkage between the operator’s network and the applications that use the network to deliver end-customer services. SDN and OpenFlow also provide tools to transform networks from an undifferentiated bit-transport commodity to a value-based resource through direct linkage with – and therefore greater relevance to – revenue-generating consumer and enterprise applications. And, it does so with both lower capex and lower opex, allowing more competitive pricing.

Big data file sets, cloud networking, and ad hoc inter-enterprise collaboration projects are all on the rise. And all of these trends result in WAN bandwidth demand peaks that are 10 to 20 times greater than their mean, with the peaks lasting anywhere from less than an hour to several weeks or more. Contracting for a private line or committed information rate sized to address the peak is at best wasteful – and for some, prohibitively expensive.

Bandwidth-on-demand services enable enterprises or cloud providers to dynamically establish or resize connectivity from the fixed or wireless access network through the core as necessary, so they pay only for what they consume. These connections can be established between subscriber locations, from the subscriber to a service gateway (e.g., a cloud data center), or from the subscriber to a third-party interconnect point.

Bandwidth-on-demand services have been offered by a limited number of operators, but the current model faces several challenges:

  • The lack of automation capabilities makes it difficult to roll out self-provisioned services and respond to time-sensitive changes in bandwidth requirements.
  • Frequent changes in a distributed control environment sometimes lead to transient overloads caused by the network having to manage traffic from multiple sources that share the same network link, resulting in congestion and instability.
  • The lack of a standard interface – requiring operators to either redesign their control applications for each vendor or to limit their services to a single vendor.

A better approach is to deploy bandwidth-on-demand services from an OpenFlow-based SDN architecture with a programmatic northbound API to allow operators to have centralized, granular control over the networking infrastructure.

With SDN, bandwidth on demand enables customers to automatically request dynamic changes to their bandwidth and other service parameters, immediately or scheduled in the future. The SDN control layer can leverage topology-aware path computation to cost effectively enable bandwidth on demand. SDN provides a real-time topological view of the network, enables network virtualization, and allows network bandwidth reservation to provide guaranteed performance on a per-connection or flow basis to meet SLA requirements.

SDN’s centralized global view of network resource supply and customer service demands paves the way for more intelligent and dynamic bandwidth-on-demand pricing that significantly increases profitability and drive new revenue streams. And the benefits of network virtualization don’t end there. It also allows operators to leverage the same networking and operational infrastructure on which they deliver traditional services to create and offer flexible bandwidth-on-demand services and new billing models.

And multiple and diverse pay-as-you-go service pricing options increase so that even smaller enterprises can afford short-term, high-capacity connectivity. With OpenFlow-based SDN, the potential is limited only by the operator’s imagination.

Edited by Alisen Downey

Mitch Auster participates on the ONF Market Education Committee. This content originally appeared as a blog for the ONF. He is senior director of market development for Ciena (