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What: Shares of Sonus Networks (NASDAQ:RBBN) have popped today by upwards of 17% after the company reported first-quarter earnings.

So what: First quarter sales totaled $63.3 million, which turned into a non-GAAP net loss of $0.02 per share. Investors were expecting just $61.1 million up top and an adjusted loss of $0.03 per share, meaning the figures were a beat relative to consensus estimates. Session border controller, or SBC, revenue was up 77% to $30 million.

Now what: Sonus added 138 new SBC customers during the quarter. The company continues to progress with its previously announced restructuring initiatives. Second-quarter guidance also came in better than expected, with revenue forecast in the range of $66 million to $68 million. The market would have been happy with just $65.1 million in sales this quarter.

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