IPv6 BGP prefix filters

Job Snijders job at instituut.net
Mon Jan 16 22:17:26 UTC 2017

On Mon, Jan 16, 2017 at 10:01:00PM +0000, Alistair Mackenzie wrote:
> So recently I've come across an issue with a large ISP announcing a
> /22 and /25 of IPv6 space. We are currently filtering <28 and >48
> which until now has worked fine for us.
> What are others using as their prefix filters in the DFZ?

The NTT global backbone (AS 2914) generally accepts (barring the other
filters) IPv6 prefixes within "2000::/3 ge 12 le 48" over eBGP.  Longer
prefixes are only accepted on customer sessions, when a valid IRR route6
object exists.

Kind regards,


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