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What happened

Shares of F5 Networks (FFIV -0.39%) rose as much as 11.3% in Thursday morning's session, following the release of strong fourth-quarter results.

So what

In the fourth quarter, F5 saw adjusted earnings rising 15% year over year to $2.11 per diluted share. Revenue increased 4.8%, stopping at $525.3 million.

The data security and application delivery specialist exceeded Wall Street's expectations across the board. Analysts would have settled for earnings of approximately $1.94 per share on sales near $520 million.

Now what

Including today's pop, F5 investors have seen their shares rising 35% so far in 2016. Data security is a hot item again, punctuated by a high-profile denial-of-service attack taking down several popular online services last Friday. F5 played an important role in recovering from that attack, putting its cloud-based Silverline mitigation product to good use.

If you'll allow me to get a little bit technical here, management sees plenty of growth opportunity in the security market. Says F5 Networks CEO John McAdam:

We believe there are several emerging market conditions that are driving an increased appeal of our products with our customers. These include the ability to orchestrate SSL traffic flows, provision our proxy based security solutions to deploy a consistent security stack across on-premise, off-premise and public cloud infrastructures, and customers moving workloads to public and private cloud architectures.

We believe these trends, combined with our new product offerings will drive our business forward in fiscal 2017 and beyond.