Selling merchandise online is not without its risks, and knows about that all too well. At one point, half of the orders placed with this online merchandiser of digital media players were fraud attempts. That's when it turned to CyberSource (NASDAQ:CYBS) for help.

Since the early days of the Internet, CyberSource has been making e-commerce safe and efficient for companies. When started using CyberSource's Decision Manager ID system, for example, it eliminated much of its fraud problem.

Perhaps that's why CyberSource has been doing well lately. During the fourth quarter, revenues increased 43% to $14.9 million. Net income was $5.2 million, and earnings per share were $0.14, up from $0.07 per share in the year-ago period. On news of those results, CyberSource's stock price surged 11.27% to $8.79.

The company's revenue model derives from licensing and transaction volume. Given that it has the infrastructure in place, this is a scalable business. And, of course, companies are increasingly using the Net for their transactions. CyberSource has reaped the benefits -- its transaction volume increased 51% over the past year to 192.7 million.

But growth hasn't come only from transaction volume. In the past quarter, the customer count for CyberSource increased by 1,800 to 13,000. Some of its customers now include Yahoo! (NASDAQ:YHOO) Hot Jobs, XM Satellite Radio (NASDAQ:XMSR), and Curves International.

What's more, CyberSource possesses a solid balance sheet and has $47 million in the bank.

Gross margins are one thing to keep an eye on moving forward, since they've been on the decline. This is the sort of business that should logically scale well, but CyberSource blamed the problem on a shift in revenue blend, which provides lower gross margin on a holistic scale but a higher margin per transaction. I think it has more to do with competition. After all, CyberSource competes with much bigger companies, not the least of which include VeriSign (NASDAQ:VRSN) and iPayments (NASDAQ:IPMT). Also bear in mind that tech companies like Google (NASDAQ:GOOG) are very smart about negotiating pricing on these things. In fact, there's talk that Google may be putting its own payment system in place -- and that could, in and of itself, pose a competitive threat.

But on the broader scale, it bears notice that as the Internet gets more dangerous because of hackers and other criminals, it becomes more critical for companies to use secure payment systems. And with more transactions taking place online, companies like CyberSource are probably going to give shareholders more growth moving forward.

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Fool contributor Tom Taulli does not own shares of companies mentioned in this article.