CALIENT unveils SDN optical topology controller

Optical switch vendor CALIENT Technologies, Inc. has announced a new software controller developed to facilitate dynamic reconfiguration of the optical network layer in cloud data center facilities via software-defined networking (SDN).

The new Optical Topology Management Controller, built on the OpenDayLight framework, also lays the foundation for hybrid network fabrics in which CALIENT's S-Series optical circuit switches augment third-party packet-based networks, the vendor explains.

In modern cloud data centers, more than 60 percent of traffic is comprised of highly persistent traffic flows that require expensive, high-capacity networks for fast and efficient delivery. These 'elephant" flows, typically caused by data replications, storage migrations, and movements of big data sets in Hadoop distributed file systems, can overflow buffers on packet switches, negatively affecing smaller, equally important and latency-sensitive "mouse" flows. Calient explained this in more detail in an article in the July/August 2014 issue of Lightwave (see "Building a data-center network with optimal performance and economy").

The first release of CALIENT's SDN-based Optical Topology Management Controller optimizes access to compute and storage nodes to achieve maximum use of these resources by allowing efficient optical topologies to be built on demand.

With the addition of traffic analysis and traffic engineering capabilities (planned for early 2015), the controller will support the full hybrid packet-optical network, in which the optical layer is reconfigured dynamically to create optical "express" paths that offload highly persistent traffic flows from the Layer 2/3 packet network.

As a result, applications and traffic pattern analysis algorithms will be able to drive the optical layer topology to achieve the highest levels of throughput and efficiency, thereby relieving the Layer 2/3 network to efficiently deliver the more transient traffic. Pure optical circuit-switched networks also offer tremendous cost savings – typically 80% less expensive than Layer 2/3 approaches at 100 Gbps, Calient asserts.

Until now, this vision of a dynamic optical layer was available only to the largest data center operators able to design their own topology management systems. CALIENT's new Optical Topology Management Controller makes this architecture available for a wider range of data centers, the company says.

"We've seen tremendous customer interest in the powerful value proposition of the dynamically reconfigurable optical layer offered by our S-Series optical circuit switches, but the stumbling block has been the lack of a controller to allow applications and traffic patterns to drive and orchestrate the new topologies," said Daniel Tardent, vice president of marketing at CALIENT. "Our new Optical Topology Management Controller is the missing link and we’re now moving ahead on a number of proof-of-concept deployments with our customers."

The new CALIENT controller will be used in conjunction with the company’s S-Series family of optical circuit switches (see "CALIENT plugs S320 optical switch into SDN with OpenFlow support" and "Calient confirms interoperability of OpenFlow API for S320 optical circuit switch"). The S320 flagship is a 320-port optical circuit switch where each switch port is transparent to bit rate and can support data speeds to 100 Gbps and beyond.

CALIENT says the Software Defined Optical Topology Manager will be available for proof-of-concept testing and system integration with third-party controller software starting January 2015. Additional functionality to enable full hybrid packet-optical networks will be announced in first quarter 2015.

For more information on optical switches and suppliers, visit the Lightwave Buyer's Guide.