Ciena’s third-quarter revenues were down compared with last year's, but the company expressed optimism about its recent acquisition of Cyan and for its future with software-defined networking (SDN).

For its third quarter, which ended July 31, Ciena reported revenue of $602.9 million as compared to $603.6 million for the fiscal third quarter 2014.

When pressed at the end of Thursday's earnings call to explain the disappointing revenues, Ciena CEO Gary Smith said, “It’s very specific elements that are particular to the individual carriers. They’re different issues with each of these carriers — some are consolidations that didn’t happen, for example. It is North America, and it is Tier 1 (three or four carriers). We think normal service will be resumed, which is what’s reflected in our guidance.”

Although top-line revenue was down, Ciena's adjusted (non-GAAP) net income for the fiscal third quarter 2015 was $50.7 million, or 37 cents per diluted common share, compared to year-ago net income of $40.9 million, or 32 cents per diluted common share.

Ciena recently acquired Cyan, which was founded in 2007 to sell packet-optical gear but began focusing on the management plane with its Blue Planet software. Of particular note was Cyan’s ability to manage other vendors’ equipment, within certain boundaries — an idea being made common by SDN.

Ciena's hope is that Cyan will put the company at the forefront of SDN and NFV. "We believe first movers will have a significant competitive advantage, as network operators around the world are already evaluating orchestration solutions,” Smith said.

Ciena also announced today that François Locoh-Donou has been appointed senior vice president and chief operating officer, effective Nov. 1, reporting to Smith. Locoh-Donou joined Ciena in 2002 and has served as senior vice president of the Global Products Group since August 2011.