Re: [Ace] Design Consideration Document as one milestone?

[Göran Selander <[e-mail]>]

Hi Hannes

Thanks for bringing this up. Let me give some context.

In the preparation for the BOF (and as was later shown in the BOF) it was
clear that there are strong opinions about the (in)feasibility of /public
key/ crypto in constrained devices. Some people state that ³there will
only be two public key operations in the lifetime of this device²,
referring to the high cost for asymmetric crypto so that they are only
used to establishing secret keys that are used thereafter. Yet other
people state ³the cost for public key crypto is negligable in today¹s
devices² 

Looking into the literature it is clear that public key crypto is in many
cases affordable, but also that it does not come for free. Moreover, when
comparing e.g. with message transmission and reception in wireless
embedded devices, you get another picture what may be expensive in
security protocol execution from an energy consumption point of view.
Section 3.2.2 discusses this in a symmetric crypto context.

This draft was put together in a rush a few days before cutoff and
contains mainly obvious things. As said, I¹m happy to use this as a basis
for a Wiki or restart the discussion. What I would like to see documented
is the (non-obvious) cost comparisons  and trade-offs between e.g.
round-trips and crypto operations, symmetric vs asymmetric operations etc.
to be able to refer to in future discussions when we need to assess the
feasibility of a particular security protocol in a constrained environment.


Göran


On 13/03/14 02:09, "Hannes Tschofenig" <[e-mail]> wrote:

>Goeran raised a question about adding a milestone for a document that
>captures assumptions and design criteria.
>
>He contributed an initial version of such a document with
>https://tools.ietf.org/html/draft-seitz-ace-design-considerations-00
>
>What does the rest of the group think about that idea?
>
>Would you be willing to review such a document?
>Would you be willing to contribute to such a document?
>
>Ciao
>Hannes
>