The continuous port scans, the worm traffic, the DDoS attacks, have to be winnowed down to something actionable.

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Also, Secure-Me-Automated Security Testing offers two free port scans (one lengthy).

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It is signature based which means it relies on a massive collection of snippets of text and code that researchers have discovered over the years are associated with unwanted network traffic, be it worms, port scans, or intrusions.

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Analysts at firms including Symantec (nasdaq: SYMC - news - people ) say an increased amount of traffic on TCP Port 445 may be the result of potential intruders scanning computers for weaknesses and that similar scans have preceded the release of other Internet worms.

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