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[IPv6]Re: [v6ops] Re: New draft: "The IPv6 Loopback Address Prefix"

Gert Doering <gert@space.net> Wed, 26 November 2025 10:53 UTC

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Date: Wed, 26 Nov 2025 11:51:57 +0100
From: Gert Doering <gert@space.net>
To: Mark Smith <markzzzsmith@gmail.com>
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CC: Gert Doering <gert@space.net>, Geoff Huston <gih902@gmail.com>, IPv6 <ipv6@ietf.org>, IPv6 Operations <v6ops@ietf.org>
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Subject: [IPv6]Re: [v6ops] Re: New draft: "The IPv6 Loopback Address Prefix"
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Hi,

On Wed, Nov 26, 2025 at 09:32:28PM +1100, Mark Smith wrote:
> It's in the context of the draft I wrote proposing a larger IPv6
> prefix. The prefix should be large enough to support subnetting it so
> that those sub-prefixes can be assigned to multiple loopback
> interfaces on a host.
> 
> A ::/96 prefix means having to subnet in an unfamiliar location within
> the IPv6 address.
> 
> A /48 for the loopback prefix would allow subnetting at the familiar
> /48 boundary, resulting in familiar /64s sized subnets that are
> assigned to different loopback interfaces on the host.

"What for"?

You need multiple loopbacks, as per your examples, if you want routing,
and this is not what would be done with this prefix.  No?

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

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