Stop IPv6 Google traffic

Mikael Abrahamsson swmike at
Wed Apr 13 06:27:13 UTC 2016

On Sun, 10 Apr 2016, Damian Menscher via NANOG wrote:

> Sorry to hear your legitimate users are impacted by captchas when trying to
> use Google web search.  This can happen when you have significant amounts
> of abuse coming from your network.  If switching to IPv4 means having more
> users share IPs, it could make the problem worse.  Instead, let's try to
> quickly address the IPv6 issue.
> Please send me your IP allocation policy (off-list is fine).  For example
> (guessing from the list at
>  - 2a01:d0::/32 is allocated by /48
>  - 2a01:d0:8000::/33 is allocated by /56
>  - 2001:67c:1874::/48 is allocated by /64
>  - ... etc (IPv4 allocation is appreciated as well, if you also provide
> customers with large ranges there)
> I can then give that hint to our automated abuse systems, which will both
> make it easier for us to catch your abusive customers, and also to avoid
> over-blocking of your AS.


just curious. Do you support the RIPE object called "assignment-size" 
for instance, indicates that each customer in this /36 is a /48. Do you 
pick this up automatically and hint your abuse system about this? Does it 
send automatically generated abuse reports to the abuse contact as well?

Mikael Abrahamsson    email: swmike at

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