Is it time to abandon bogon prefix filters?

Marshall Eubanks tme at
Fri Aug 15 08:33:45 CDT 2008

On Aug 15, 2008, at 9:26 AM, Randy Bush wrote:

>> In other words, our earlier estimate of 60% was way off...  you can
>> get 92.1% effectiveness at bogon filtering by just dropping 1918
>> addresses, a filter that you will never have to change.
> my read is that the 60% was an alleged 60% of attacks came from *all*
> bogon space.  this now seems in the low single digit percentge.  of
> that, the majority is from 1918 space.

If (trying to reverse engineer this thread) previously 60% of all  
came from bogonspace, and now only 2.96% do, that does not mean that
if the bogon filters are removed, that number will stay at < 3 %. It may
just mean that the filtering is effective.


> randy

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