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Re: [TLS] [ALU] Re: extending the un-authenticated DTLS header

"Kraus Achim (INST/ESY1)" <Achim.Kraus@bosch-si.com> Wed, 16 November 2016 10:21 UTC

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From: "Kraus Achim (INST/ESY1)" <Achim.Kraus@bosch-si.com>
To: "tls@ietf.org" <tls@ietf.org>
Thread-Topic: [TLS] [ALU] Re: extending the un-authenticated DTLS header
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Date: Wed, 16 Nov 2016 10:21:41 +0000
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Subject: Re: [TLS] [ALU] Re: extending the un-authenticated DTLS header
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Hi,

I'm still wondering, why the "clashing" calculations (section 4) are only based on the number of clients and not also on the length of the hash chain.
As I understood the hash chain, the DTLS server and client calculates a list of CIDs. Though the client chose one, the server has to prepare for the (left) list of CIDs. So even assuming that in average half of the list is already used, I think the length of that list has influence on the clashing.

Mit freundlichen Grüßen / Best regards

Achim Kraus

Bosch Software Innovations GmbH
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-----Ursprüngliche Nachricht-----
Von: TLS [mailto:tls-bounces@ietf.org] Im Auftrag von Fossati, Thomas (Nokia - GB)
Gesendet: Dienstag, 15. November 2016 08:08
An: Martin Thomson <martin.thomson@gmail.com>; Eric Rescorla <ekr@rtfm.com>
Cc: Hannes Tschofenig <Hannes.Tschofenig@arm.com>; tls@ietf.org
Betreff: Re: [TLS] [ALU] Re: extending the un-authenticated DTLS header

On 15/11/2016 03:51, "TLS on behalf of Martin Thomson"
<tls-bounces@ietf.org on behalf of martin.thomson@gmail.com> wrote:
>On 15 November 2016 at 10:16, Eric Rescorla <ekr@rtfm.com> wrote:
>>> I'd be interested in an analysis of the potential privacy impacts of 
>>> this. Isn't this more or less the same as doing SPUD-for-DTLS? (If 
>>> not, sorry for dragging in controversy:-)
>>
>>
>> It would no doubt depend what you put there.
>
>Which is why I'm interested in seeing Nikos' (unpublished?) draft.

Published:
https://tools.ietf.org/html/draft-mavrogiannopoulos-tls-cid-00


Working copy:
https://thomas-fossati.github.io/draft-tls-cid/

Slides for today, "DTLS Optimizations for IoT Deployments":
https://www.ietf.org/proceedings/97/slides/slides-97-tls-dtls-optimizations
-for-iot-deployments-00.pptx

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