Re: [Doh] [Ext] Privacy Considerations Text (#2)

[Mateusz Jończyk <[e-mail]>]

W dniu 22.06.2018 o 17:57, Mateusz Jończyk pisze:
> W dniu 22.06.2018 o 17:42, Paul Hoffman pisze:
>> On Jun 22, 2018, at 8:34 AM, Mateusz Jończyk <[e-mail]> wrote:
>>> W dniu 21.06.2018 o 20:43, Patrick McManus pisze:
>>>>
>>>> The privacy considerations of using the HTTPS layer in DoH are
>>>> incremental to those of DNS over TLS. DoH is not known to introduce
>>>> new concerns beyond those associated with HTTPS.
>>>
>>> I have been thinking that a DoH client would open a long-running connection to a
>>> DoH server. In such a case, request correlation could be simple and we should
>>> drop the "is not known to introduce new concerns" sentence.
>>
>> Both RFC 7766 (DNS in TCP) and RFC 7858 (DNS in TLS) recommend opening long-running connections, and explain the operational pros and cons of doing so.
>>
> 
> OK, now I have read that passage again and understand it.
> I would argue that this should be discussed explicitly in the "Privacy
> considerations" section.
> 

I would propose to add the following text:

	Because of performance reasons, DOH clients are advised to open
	long-running connections to the DOH server. However, in such a case the
	server is able to correlate all the requests within a connection.
	Therefore it is advisable for DOH clients to close and reopen the
	connection to the DOH server e.g. every hour or when outside IP address
	changes - to make request correlation more difficult.

I am happy to live in the EU. AFAIK our law makes doing such request
correllation for tracking purposes illegal in most cases.

Greetings,
Mateusz Jończyk