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What: Shares of Aruba Networks (NASDAQ: ARUN) have plunged today by as much as 30% after the company reported earnings held back by intensifying competition.

So what: Revenue in the quarter came in at $147.1 million, which translated into non-GAAP earnings per share of $0.11. Earlier this month, Aruba slashed its guidance, and the figures were in line with the reduced forecast. Competitive fears also further rattled investors.

Now what: CEO Dominic Orr attributed weakness to a "heightened level of competition and bundling strategy" from Aruba's largest competitor, Cisco Systems, along with a tough macro environment. The pressure is leading to order delays from Aruba's customers, as Cisco aggressively bundles and cuts prices. Cisco's own earnings release came in better than expected, suggesting that it's seeing success in stealing market share from competitors. Aruba has seen nearly a dozen analyst downgrades in the wake of the results.

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