Re: [Dots] Mirja Kühlewind's Discuss on draft-ietf-dots-requirements-18: (with DISCUSS and COMMENT)

["Teague, Nik" <[e-mail]>]

Hi,


On 21 Feb 2019, at 10:58, Mirja Kuehlewind (IETF) <[e-mail]> wrote:

>>> 3) In SIG-006 you say:
>>> "      Due to the higher likelihood of packet loss during a DDoS attack,
>>>     DOTS servers MUST regularly send mitigation status to authorized
>>>     DOTS clients which have requested and been granted mitigation,
>>>     regardless of client requests for mitigation status."
>>> 
>>> Please note that this is only true if a not-reliable transport is used. If a
>>> reliable transport is used, data is received at the application level without
>>> loss (but maybe some delay) or the connection is terminated (if loss is too
>>> high to retransmit successfully).
>>> 
>> 
>> [Med] The requirement as worded is OK. 
> 
> I disagree, because as I said if a reliable transport is used this is not true. Maybe you can adapt this sentence slightly to clarify that you probably had a scenario in mind where an unreliable transport is used

The key part here is ‘packet’ vs ‘data’ - packets will be lost on congested links regardless of data integrity.  This may degrade connection re-establishment with tcp and cause data loss in an unreliable transport.