Strange DNS traffic

[Maarten Claes <maarten.claes () gmail com>]

Hi list,

I've seen some strange (blocked) dns traffic on my firewall:

Random source ips are requesting a PTR lookup of the receiver's ip
address. This is not normal DNS traffic as a dig -x <ip> +trace
shows that the DNS provider for that IP range has the answer for that
hosts and not the host itself.

Is this some kind of dns probing attempt/attack attemp/fingerprinting..

Thanks for your comments!

Maarten.