Sourcefire acquires start-up Immunet for $21 million, including $17 million paid at closing and $4 million expected to be paid over the next 18 months. Sourcefire CEO John Burris calls Immunet a disruptive innovator in delivering cloud-based solutions with over 750,000 users in 192 countries. Immunet’s approach is to leave anti-virus signatures in the cloud in a platform that Sourcefire expects to use for threat information-sharing over time.”]

