Re: [v6ops] Scope of Unique Local IPv6 Unicast Addresses (Fwd: New Version Notification for draft-gont-6man-ipv6-ula-scope-00.txt)

Gert Doering <> Wed, 06 January 2021 16:26 UTC

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Date: Wed, 6 Jan 2021 17:26:52 +0100
From: Gert Doering <>
To: Fernando Gont <>
Cc: Philip Homburg <>,, IPv6 Operations <>
Subject: Re: [v6ops] Scope of Unique Local IPv6 Unicast Addresses (Fwd: New Version Notification for draft-gont-6man-ipv6-ula-scope-00.txt)
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On Wed, Jan 06, 2021 at 12:42:13PM -0300, Fernando Gont wrote:
> And, as noted, there are concrete implications:
> RFC4007 says ULAs are non-global, RFC4193 says that ULAs are global, and 
> a Python library says ULAs are non-global. I don't think we want that.

On a tangent, I wonder why this is relevant at all.

Why should applications, or anything that is not an admin, care if an
address is a ULA or a GUA?

(I can see the bit about "tools that enter GUAs in the global DNS",
but this is very special anyway - because "DNS" might not be "global",
so general "refuse to put ULA into DNS" is not correct behaviour either)

Consistent terminology is important, true, and if we just want to make
sure that something can properly flag a ULA different than a GUA, we
could just introduce

  "mid-range scoped"

or rename the scopes to be 0 (link-local), 5 (mid-range), 10 (global)...

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

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