Honeynet Alliance Charter Question

Greetings all,
    I was wondering if someone could explain to me the meaning and 
purpose of the honeynet alliance requirement 4.8 involving data capture.

 From this page:

http://www.honeynet.org/alliance/charter.txt

"4.8  Organizations that deploy honeynets and related technologies for
     data capture must use passive means.  No active means of data
     capture are acceptable under the Alliance.  "

What types of activity would be considered "passive" data capture as 
opposed to "active".  I see how tcpdump would be considered passive, 
while something like nmap would be considered active, but is there a 
more formal definition/description that could be used to help classify 
data capture methods when they aren't so obvious?  Having a better 
understanding of the intent of this requirement might help me understand 
how to interpret it as well.  Please let me know any thoughts you might 
have. 
Thank you for any assistance, -Adam


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Clatto Verata Nicto