Re: [Tsv-art] [v6ops] [Last-Call] Tsvart last call review of draft-ietf-v6ops-ipv6-ehs-packet-drops-05

[Fernando Gont <[e-mail]>]

On 23/2/21 13:54, Mark Smith wrote:
> On Wed, 24 Feb 2021 at 02:51, Fernando Gont <[e-mail]> wrote:
>>
>> Hi, Tom,
>>
>> On 23/2/21 11:34, Tom Herbert wrote:
>> [...]
>>> >From the draft:
>>>
>>> "Unless appropriate mitigations are put in place (e.g., packet
>>> dropping and/or rate- limiting), an attacker could simply send a large
>>> amount of IPv6 traffic employing IPv6 Extension Headers with the
>>> purpose of performing a Denial of Service (DoS) attack"
>>>
>>> That is clearly recommending a mitigation which is to drop packets or
>>> rate-limit.
>>
>> No, We're just stating the obvious. If we were performing a
>> recommendation, the text would be something like "IPv6 implementations
>> should". And we'd also be using RFC2119 speak... and the document would
>> be BCP.
>>
> 
> It reads like an implied recommendation to me.
> 
> It's stating possible prevention measures, and then the consequences
> of not doing them. That implies the stated prevention measures are
> recommended. (e.g. "If you aren't careful with a knife, you could cut
> yourself (so be careful with a knife)").

I think you're reading more from the draft that what we have written or 
meant.

Your example is a good one, and has indeed two parts:

    "If you aren't careful with a knife, you could cut yourself"

This is a *fact* and I don't think there's much room for debate around it.


   "(so be careful with a knife)"

*This* is advice.


Our document contains the former (a fact), but not the later (advice).

Thanks,
-- 
Fernando Gont
SI6 Networks
e-mail: [e-mail]
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