This week, the Pentagon said computer networks in the United States, Germany, Britain and France were hit last year by what they call "multiple intrusions," many of them originating from China.

So for each potentially intrusive connection, Snort needs a rule (or rules that cover multiple related intrusions).

In respect to the issue of alarms flooding, which is resulted from multiple detection sensors in terms of intrusions, this article proposes a novel on-line model on alarms clustering and fusion.