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

Fernando Gont <> Sat, 20 February 2021 16:09 UTC

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To: Gert Doering <>
Cc: Brian E Carpenter <>, "Manfredi (US), Albert E" <>, IPv6 Operations <>, "" <>
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From: Fernando Gont <>
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Date: Sat, 20 Feb 2021 11:46:31 -0300
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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 20/2/21 11:09, Gert Doering wrote:
> Hi,
> On Thu, Feb 18, 2021 at 09:58:29PM -0300, Fernando Gont wrote:
>> On 18/2/21 21:36, Brian E Carpenter wrote:
>>> So, my thought (and it belongs on this thread OR the 'IPv6 addressing: Gaps?' one) is something like:
>>> We should abolish, delete, expunge and deprecate the word "scope" from all IPv6 documents. It clearly doesn't have an agreed meaning, so it is worse than useless.
>> FWIW, wfm. :-)
> Seconded.

That said, just ran into this I-D, that also makes use of "scope": 

>> (Modulo: the multicast folks do use "scope" in a more "successful" way,
>> IIRC?)
> Their definitions are at least somewhat more clear on what a "scope" is -
> send a packet to that address, and this is how far it will get.
> In practice, how much IPv6 multicast is there which is not "node" and
> "link" scoped?  Or, to be even more picky, not "link" scoped?

I guess that depends a lot on the deployment environment. For the 
general case, the answer is "hardly any". But then I'm told that in e.g. 
some stock markets they are *required* to emply multicast to spread some 

Fernando Gont
SI6 Networks
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