Another quarter, another big beat from Palo Alto Networks (NYSE:PANW). But judging by the initial 4% plunge in Monday's after-hours trading, the market doesn't seem particularly impressed by the data security specialist's latest results.

The numbers
Continuing last quarter's impressive outperformance, Palo Alto Networks saw fiscal first-quarter 2015 revenue climb 50% year over year to a company-record $192.3 million, including 34% growth in product revenue to 101.5 million, and 76% growth in recurring subscription revenue to $43.7 million. On a GAAP basis, this translated to a net loss of $30.1 million, or $0.38 per diluted share, which is significantly wider than the $0.11-per-share GAAP loss it turned in during the same year-ago period. On a non-GAAP basis, however, Palo Alto achieved net income of $0.15 per diluted share.

For perspective, both figures are also well ahead of Palo Alto's own guidance provided back in September, which called for revenue of $178 million to $182 million, and adjusted earnings of $0.12 per share. And analysts, on average, were only modeling earnings of $0.12 per share on sales of $181.7 million.

Meanwhile, Palo Alto's billings grew 52% year over year to $240.5 million, and deferred revenue grew 69% year over year to $470.7 million -- both also new company records. In addition, Palo Alto generated $74.9 million in cash flow from operations and -- after accounting for roughly $5.9 million in property and equipment purchases -- $69 million in free cash flow. This helps Palo Alto at least partly finance continued heavy spending on both R&D ($37.3 million) and sales and marketing ($106.4 million), which are each crucial in its efforts to grab early market share in the burgeoning cyber-security industry.

A "new era in malware"
"In today's increasingly complex threat environment, enterprise customers recognize that a true, integrated, and automated platform delivering prevention capabilities offers superior security with a superior total cost of ownership advantage," said Palo Alto Networks CEO Mark McLaughlin.

Increasingly complex, indeed. Earlier this month, for example, Palo Alto published a report on a new family of malware it discovered called WireLurker, which was used to trojanize hundreds of OS X applications, and downloaded over 356,000 times on a prominent third-party Mac application store in China. Further, Palo Alto says WireLurker "marks a new era in malware attacking Apple's desktop and mobile platforms," in large part given its unrivaled scale and novel ability to spread from infected OS X computers to non-jailbroken iOS devices through a USB connection.

CFO Steffan Tomlinson elaborated on the positive consequences Palo Alto's demonstrated market leadership, pointing to "robust new customer acquisitions and expansion within our existing customer base" as driving its record results.

On guidance
Perhaps it should come as no surprise, then, that Palo Alto expects current quarter revenue and adjusted earnings per share to be in the ranges of $200 million to $204 million, and $0.16 to $0.17, respectively. Once again, the midpoint of both ranges sits ahead of Wall Street's expectations for fiscal second-quarter earnings of $0.16 per share, and revenue of $198.1 million.

So why are shares down right now?

First, keep in mind that Palo Alto stock jumped 4% in Monday's trading in anticipation of the report, so the after-hours decline essentially gives back those short-term gains. What's more, note that as of Monday's close Palo Alto Networks stock had almost doubled year to date in 2014 and traded at a lofty 81 times next year's estimated earnings and 14.5 times trailing-12-month sales.

Of course, that doesn't mean patient, long-term investors can't still reap big rewards by holding Palo Alto stock. In the end, to me this looks like an undeniably strong performance from a promising young company, and shareholders should have every reason to expect more of the same going forward.

Steve Symington owns shares of Apple. The Motley Fool recommends Apple and Palo Alto Networks and owns shares of Apple. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.