Preventing the 'other' type of zone transfer

[Stafford, Paige L.]

210.146.35.35 stepped through our entire 128.219/16=20
address space yesterday asking for reverse DNS lookups. =20
It started at 16:06 and ended at 20:34.  This is the=20
equivalent of a zone transfer.=20
 =20
I'm looking for a clever way of stopping this.  And if we=20
can't, we want to at least slow it down.  Creating dummy=20
records for the unused IP addresses has not been effective. =20

*Any* ideas you have would be most welcome.
=20

Paige Stafford
DNS administrator, ORNL
staffordp1 at ornl.gov