Re: [v6ops] Implementation Status of PREF64

Gert Doering <> Wed, 13 October 2021 17:34 UTC

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Date: Wed, 13 Oct 2021 19:34:17 +0200
From: Gert Doering <>
To: Gert Doering <>, "Pascal Thubert (pthubert)" <>, v6ops list <>, Lorenzo Colitti <>
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Subject: Re: [v6ops] Implementation Status of PREF64
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On Wed, Oct 13, 2021 at 10:23:28AM -0700, Owen DeLong wrote:
> > Thinking we have arbitrary number of /64s to burn will have a hard landing
> > when reality comes along.
> Will it? Here???s reality???
> More than enough /48s in 2000::/3 (1/8th of the total space) to hand out a few
> hundred to every building now in existence or likely to ever exist.

You're overlooking intermediate hierarchies, and loss involved with that.

Can it be made to work?  Of course.

Can we have another quintillion for everybody's k8s clusters, and another
one for every desktop PC with VMs on it?  Of course.

Will we wake up to see that the start of this plan wasn't the best of ideas?

So, no, assigning whole /64s to large-numbered device types (unless they 
serve as routers for one or more subnets, in which case I *do* support 
delegating at least one standard-subnet-size per subnet) is not something
I think we should do.  Balance needs to be found.

Gert Doering
        -- NetMaster
have you enabled IPv6 on something today...?

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