Re: [Ace] CWT-PoP & Multiple PoP keys

Ludwig Seitz <ludwig.seitz@ri.se> Wed, 20 June 2018 07:14 UTC

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From: Ludwig Seitz <ludwig.seitz@ri.se>
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Date: Wed, 20 Jun 2018 09:14:13 +0200
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Archived-At: <https://mailarchive.ietf.org/arch/msg/ace/hEcb5-U37SvXz5P8nMEYdR3p8dU>
Subject: Re: [Ace] CWT-PoP & Multiple PoP keys
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On 2018-06-20 08:57, Hannes Tschofenig wrote:
> Hi Jim,
> 
> I had a chat with Mike about relaxing the CWT-PoP spec to allow multiple 
> PoP keys in a single CWT token.
> 
> He is concerned about the departure from RFC 7800 and, after giving it a 
> bit more thoughts, I believe there is an issue. Initially, when we 
> started the work our promise was that this is really just an alternative 
> encoding of RFC 7800. With changes like those we are obviously breaking 
> that concept. Having multiple keys within a single CWT is a corner case 
> and I am not sure anymore whether I indeed want to go into that 
> direction. In our implementation we are also not using multiple keys in 
> a single CWT either.
> 
> Ciao
> 
> Hannes
>

I agree that having multiple PoP keys in cnf for CWT-PoP seem like 
overkill. After all this is a draft aimed at constrained environments.
I also sympathize with Mike's suggestion to keep CWT-PoP aligned with 
RFC 7800.

/Ludwig


> IMPORTANT NOTICE: The contents of this email and any attachments are 
> confidential and may also be privileged. If you are not the intended 

Sending confidential email to a public mailing list again Hannes? You 
are a rebel ;-)


-- 
Ludwig Seitz, PhD
Security Lab, RISE SICS
Phone +46(0)70-349 92 51