Juniper Networks today announced it is buying BTI Systems, a player in the optical networking arena. And Juniper is linking the purchase to its wide-area network (WAN) software defined network (SDN) controller.

“We expect the acquisition will allow Juniper to accelerate the delivery of open and automated packet optical transport solutions that integrate with our NorthStar controller and include network management features that enable end-to-end provisioning of new services,” wrote Jonathan Davidson, head of Juniper’s development and innovation group, in a blog posting.

The NorthStar controller is a traffic optimization WAN-SDN controller that automates the creation of traffic-engineering paths across the network. It provides control over IP/MPLS flows in large service provider and enterprise networks.

BTI President and CEO Colin Doherty wrote on the BTI website that the company has focused on providing metro, data center interconnect (DCI), and cloud network infrastructure to a growing customer base.

At the SDN & OpenFlow World Congress last November, BTI demonstrated how it had opened up its BTI 7800 optical platform to third-party software that service providers could control with an OpenDaylight controller.

“Juniper’s recognizing the importance of an optics play,” says Michael Capuano, VP of marketing with Infinera. “They’ve tried with hiring optical talent and partnerships with Coriant and ADVA but really without meaningful success. Buying BTI validates the importance of optical technology in next- generation architectures.”

The service provider market is huge for Juniper, and service providers are virtualizing everything they can, which is a threat to Juniper’s router business. An SDN controller can look at multiple layers and can keep some traffic off routers and keep it on optical. With BTI, Juniper may be able to play in both realms.

The terms of its BTI purchase were not disclosed. It's slated to close in the second quarter of this year.