On Mon, 28 Apr 2003, Sean Donelan wrote:
On Mon, 28 Apr 2003, McBurnett, Jim wrote:
I am not a BGP Guru by any means but as I see it: there are more than 25 /8 that should not be routed at all... And they are easily summarized.. some can be /6 or less... I never tried that.. But should work....
If Rob wanted to do it right :-)
In 2001, approximately 33.5% of IPv4 address space was being announced in the global routing table. If you wanted to do complete negative filtering, you need to filter 66.5% of the IPv4 address space.
But probably 50% or more of that is contained in large aggregatable blocks... Steve
http://www.apnic.net/stats/bgp/TOTAL/totaladd.html
Unfortunately, all we have is a rather blunt tool. Its a bit like trying to fight credit card fraud by rejecting any card that doesn't begin with a 4 (Visa) or 5 (partial Mastercard range). It may work as a limited data entry check, but its not enough.