It's 3 p.m. Do you know where your company's employees are? Probably not, because a whole lot of them are paging through Facebook, and not for business purposes either.   

Twice a year, security vendor Palo Alto Networks logs the applications running over its customers' networks for a week and issues an Application Usage and Risk Report. This time around, the vendor found 931 applications running over the networks, and Facebook was the sixth most frequently accessed. Combining applications for socializing, P2P, browser-based filesharing, personal webmail and IM into one category, PAN identified 224 apps, and discovered that nearly one-fourth of corporate bandwidth was used up by them.

"More often than not, these applications are unmonitored and uncontrolled, which introduces outbound risks that include data loss and compliance issues," the report reads. "The inbound risks are equally significant--many of these applications are known to transfer malware (Zeus, Conficker, Mariposa) and have had known vulnerabilities."

The amount of bandwidth corporations spend on social media doubles from year to year, according to the vendor's figures, and this time around Facebook took up almost 80 percent of that bandwidth.

"It is no surprise that Facebook is the social networking application of choice worldwide," the report reads. "What is surprising is the dominance that the Facebook usage exhibits from a bandwidth consumption perspective. Excluding the mail and chat functions, Facebook traffic alone is 500 percent greater than the other 47 social networking applications combined."

What also may come as a surprise to some companies is that employees are not exactly doing the company's business while on Facebook. As Palo Alto Networks puts it, the "The Facebook traffic patterns contradict certain assumptions about how the application is used while at work."

It turns out that most of the Facebook traffic goes toward looking at pages, while just 1 percent of the traffic is for posting: "In short, while at work, users are voyeurs."

For more:
- see Palo Alto Network's latest Application Usage and Risk Report

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