Family: Wife, Anna, and four children

Hobbies: Astronomy and sailing

Fun fact: Started Sourcefire in his living room (then in Carroll County)

How Sourcefire and Cisco compare

SourcefireCisco

Headquarters:ColumbiaSan Jose, Calif.

2012 revenue:$223 million$46 billion

2012 profit:$5 million$8 billion

Employees: About 650About 74,000

Founded: 20011984

Source: Company filings. Cisco's 2012 fiscal year ended July 28, 2012.