Re: [TLS] DTLS 1.3

Stephen Farrell <> Thu, 07 July 2016 11:57 UTC

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To: Nikos Mavrogiannopoulos <>
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From: Stephen Farrell <>
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Subject: Re: [TLS] DTLS 1.3
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On 07/07/16 12:52, Nikos Mavrogiannopoulos wrote:
> On Thu, 2016-07-07 at 10:37 +0100, Stephen Farrell wrote:
>> Hiya,
>> Just on this one thing...
>> On 07/07/16 09:13, Nikos Mavrogiannopoulos wrote:
>>>  does not make the situation any worse
>>> than we have today.
>> I don't accept that is the correct goal. That form of
>> argument is what lead to us standardising the HTTP
>> Forwarded header field, which IMO was a disimprovement.
>> (An argument I lost in the end in that case [1], but
>> 'twas close, and back in 2012 so might go the other
>> way today;-)
>> I would argue that the correct goal is to make things
>> better whenever possible, with that being especially
>> important for protocols like (D)TLS on which many
>> other things depend.
>> I do agree that any scheme developed would need to
>> meet the state management requirements of servers.
>> I'm not convinced those requirements call for a new
>> super-cookie though:-)
> I understand your point, I'm not fully convinced by that argumentation.
> I may be wrong of course, but I'll try to explain my point. Indeed
> putting privacy first should be a goal of TLS/DTLS, but to the extent
> it covers the protocol goals. What you propose is to make a stream
> anonymous, untrackable. 

Totally wrong, sorry. What I propose is not adding new ways to
allow a network observer to track a tls client using the same
tls session over multiple transport layer connections, unless
that is really unavoidable.

Exaggerating my argument is not useful. Not is it at all convincing.


> However, that (anonymity or untrackability of
> the stream) was never a stated goal of TLS/DTLS. In fact TLS is by
> definition trackable over TCP and one can see in the clear the IPs of
> the two peers communicating. That doesn't change by switching to DTLS,
> except for unfortunate situations of routers losing state and client
> roaming, which current servers cannot easily cope with, and that's the
> problem I attempt to address.
> I think the principle of doing one simple thing and doing it well,
> applies to protocols as well. TLS and DTLS provide a layer of
> confidentiality and authenticity. Anonymity, untrackability can be
> provided by other protocols focused on that such as TOR.
> regards,
> Nikos