Security Software IPOs: Where'd They Go?

For companies like IronPort and others, the Street will be looking for long-term, double-digit revenue growth, a clear path to profitability and solid management teams that have compliance issues in order.

"You want to stay private to get enough legs under the stool, to make sure you're going to be a high performer and consistent," Collins said.

At this point, of the 700 privately-held security firms, there are perhaps four or five that have a promising shot at going public, Morgan Stanley's Kuper says. (Most of those 700 firms, it should be noted, intend to stay private).

One such candidate, CipherTrust, was just picked up by Secure Computing (SCUR Quote) on Tuesday. Sourcefire, Webroot and Postini, among others, are also considered possibilities for going public.

"Consolidation will continue in security, but I also think the threat landscape evolves quickly enough that there will be other opportunities," Allen said.

"As new technology is rolled out it will create new problems," Kuper says. His firm does and seeks to do business with the companies it covers.