Re: [MLS] [new-work] WG Review: Messaging Layer Security (mls)

[Peter Saint-Andre <[e-mail]>]

On 5/24/18 8:05 AM, Eric Rescorla wrote:
> 
> 
> On Mon, May 14, 2018 at 8:55 AM, Peter Saint-Andre <[e-mail]
> <mailto:[e-mail]>> wrote:
> 
>     Two points:
> 
>     1. It would be helpful to specify the expected capabilities of devices
>     on which the resulting protocol might be deployed, such as only personal
>     devices (e.g., phones and tablets) or also Internet of Things devices.
>     If IoT devices are in scope (I hope they are!), then citing RFC 7228
>     would be good:
> 
>     https://datatracker.ietf.org/doc/rfc7228/
>     <https://datatracker.ietf.org/doc/rfc7228/>
> 
> 
> I think the default is we assume reasonably powerful general purpose
> computers, 

Constrained devices are indeed hard to design for (and there are many
dimensions of constraint - code size, memory, storage, battery, etc.). I
wouldn't necessarily argue for supporting Class 0 devices (which
according to RFC 7228 are "very constrained sensor-like motes"), but
Class 2 devices (which are "fundamentally capable of supporting most of
the same protocol stacks as used on notebooks or servers") would be
great. I'm not sure where to draw the line and whether to include Class
1 devices (which "are quite constrained in code space and processing
capabilities, such that they cannot easily talk to other Internet nodes
employing a full protocol stack such as using HTTP, Transport Layer
Security (TLS), and related security protocols and XML-based data
representations").

> so if people want IoT to be designed for -- which it
> shouldn't, IMO -- then that would have to be stated in the charter.

No matter what we decide, it would be good to make that explicit in the
charter.

Peter