Source: Ciena.

Telecom-grade networking equipment maker Ciena (NYSE:CIEN) reported results for the second quarter of fiscal year 2014 this morning and shares jumped as much as 17% higher on the news.

Analysts were looking for adjusted earnings of $0.13 per share on roughly $560 million in total sales. Ciena's revenue was in line with Street projections, but earnings jumped all the way to $0.17 per share. That's up from $0.02 of adjusted earnings per share on sales $508 million in the year-ago quarter.

Non-GAAP gross margins expanded by 0.6% year-over-year, and now stand at 43.1%. Operating margins jumped 68% higher, to 6.2%.

Strong demand for Ciena's cutting-edge converged packet optical products provided the bulk of the company's growth, while commodity products in the optical transport division continued to decline.

One customer accounted for 21.5% of Ciena's total revenue. This large customer was not explicitly named in the press release, but AT&T has traditionally been Ciena's biggest buyer. Between 2011 and 2013, AT&T was the only Ciena customer to exceed 10% of the company's sales in any given year, with the ratio of AT&T sales to overall revenues ranging between 13% and 18%.

Looking ahead, Ciena expects third-quarter sales near $600 million. That would be about 3% above the current analyst view.

Ciena CEO Gary Smith hasn't changed his view from the first-quarter report's optimistic statements. "As a direct result of our expanding role and reach in the industry, we delivered strong financial results in both our second quarter and first half of fiscal 2014," Smith said in a statement released today.

Anders Bylund has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days.

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