With the spring thaw, new life emerges from its slumber, and it seems that companies are following suit. After a long, cold recession, we’re starting to see hopeful signs of blossoms, particularly in security. Proofpoint broke the ice in December 2011 with a planned $50m IPO, and Splunk followed in January with its own $125m debut. (Both of those companies are expected to price next week.) Although SafeNet pulled its offering last month, the forward momentum is clear, with Palo Alto Networks’ filing being the latest and largest at $175m.

Palo Alto has enjoyed a high profile in the industry, with its application control features that prompted many other vendors to add them to their own lines. Despite the current competition, the company enjoys an enviable popularity rating: it was listed at the top of the ‘exciting vendors’ list in the latest security survey of IT executives by TheInfoPro, a service of 451 Research, and with 44% of respondents saying they would be spending more money on application-aware firewalls in 2012, Palo Alto looks to benefit most from the firewall fever.

(Read the full report here. A 451 Research subscription is required but a free trial is available here).