[AusNOG] IPv6 reverse DNS and Mail ...

[Mark Delany]

On 20May13, Daniel O'Connor allegedly wrote:

> I wonder how much spam you block by rejecting submissions from hosts with incorrect/unconfigured reverse DNS entries.
> 
> I also wonder how much ham you block incorrectly..

I wonder as well. Last time I looked very little of China's IP
allocations have reverse entries and, given their GDP is said to reach
the USA's in a few years and given they are Australia's largest
trading partner, blocking or quarantining based solely on a lack of
reverse is going to mis-identify a lot of genuine Chinese traffic.

I know people love to see reverse entries and it makes traceroutes far
more interesting, but since they aren't essential to the function of
anything, maintenance of reverses has always, and will always, be
haphazard at best. Much as the Internet Police would like to believe
otherwise.


Mark.