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

Ted Lemon <> Sun, 14 February 2021 21:32 UTC

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From: Ted Lemon <>
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Date: Sun, 14 Feb 2021 16:32:33 -0500
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Cc: Brian E Carpenter <>, Fernando Gont <>, IPv6 Operations <>, "" <>
To: David Farmer <>
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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 Feb 14, 2021, at 4:00 PM, David Farmer <> wrote:
> So I recommend a small update to RFC4007, further quantify the necessary uniqueness;
> Global scope, for uniquely identifying interfaces anywhere in the Internet *or within the span of reachability for local-use addresses.*

I think this whole discussion may have something to do with why site-local was deprecated, although I’m just guessing because I didn’t participate in that discussion.

My question to you is this: how does your proposed update help anybody to understand?

If we were to update the text, I would suggest something like this:

Global scope, for uniquely identifying interfaces anywhere on the Internet. Note that when we say an address is “globally unique,” this is a definitional assertion: such an address is to be treated as globally unique by hosts and routers. Mechanisms for ensuring that this definitional assertion is not violated exist for each type of globally scoped address, and in some cases rather than ensuring that a globally /scoped/ address is in fact unique, these mechanisms ensure that the use of such addresses is constrained to contexts in which they are /known/ to be unique.