Re: [v6ops] Stateful SLAAC (draft-ietf-v6ops-unique-ipv6-prefix-per-host)

Fernando Gont <> Fri, 10 November 2017 20:21 UTC

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Subject: Re: [v6ops] Stateful SLAAC (draft-ietf-v6ops-unique-ipv6-prefix-per-host)
To: Fred Baker <>, Lorenzo Colitti <>
Cc: IPv6 Operations <>, "" <>, "" <>, "" <>,
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From: Fernando Gont <>
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Date: Fri, 10 Nov 2017 17:23:29 -0300
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Hi, Fred,

On 11/10/2017 01:12 AM, Fred Baker wrote:
>> On Nov 9, 2017, at 8:28 AM, Lorenzo Colitti <> wrote:
>> On Tue, Nov 7, 2017 at 6:13 AM, Fernando Gont <> wrote:
>> While reviewing this document a few days ago, I found that Section 4
>> (page 5) contains what is a protocol spec, rather than an operational
>> BCP. It contains rules regarding how to set the link-layer address (to a
>> unicast address) for IPv6 multicasted RAs, and how a SLAAC router should
>> now remember which prefix has been "leased" to which node -- something
>> that seems to be way outside of the v6ops charter, and that should have
>> been done in 6man, instead.
>> I don't see how this is a protocol change. Sending RAs unicast is already allowed by RFC 4861, so this is just an operational practice.
> I understand the concern to be sending to a multicast address at the network layer and a unicast address at the link layer. If 4861 allows the RA to be sent unicast, it is probably unicast at both layers. I suspect that if we change to doing what 4861 describes we'll be fine.

At which point you realize that know you have to no implement the
graituous  all-nodes RAs, and it becomes evident that you are changing
the spec.

THe main issue is not this but, as the subject implies, this document
making SLAAC stateful.

But, anyway, it should be easy to have all of us converge on something:
the whole discussion boils down to whether this is or is not a protocol

So, my request would be. For folks arguing that this document is not a
protocol spec, could you please provide a definition of what a protocol
is, and subsequently explain why/how such definition does not encompass
this document?

Fernando Gont
SI6 Networks
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