Re: [Ace] Murray Kucherawy's Discuss on draft-ietf-ace-mqtt-tls-profile-15: (with DISCUSS and COMMENT)

[Benjamin Kaduk <[e-mail]>]

On Wed, Mar 09, 2022 at 10:35:01PM -0800, Murray Kucherawy via Datatracker wrote:
> Murray Kucherawy has entered the following ballot position for
> draft-ietf-ace-mqtt-tls-profile-15: Discuss
> 
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> 
> ----------------------------------------------------------------------
> DISCUSS:
> ----------------------------------------------------------------------
> 
> This should be quick to resolve.  In Section 3.2:
> 
>    The Broker MUST NOT forward messages to unauthorized subscribers.
>    There is no way to inform the Clients with invalid tokens that an
>    authorization error has occurred other than sending a DISCONNECT
>    packet.  Therefore, the Broker SHOULD send a DISCONNECT packet with
>    the reason code '0x87 (Not authorized)'.
> 
> This seems like a contradiction.  How is that SHOULD not a MUST?

I suppose you could also be less informative and just drop the transport
connection with no DISCONNECT (or simply hold it open while passing no traffic).
I think that's what I had in mind when I reviewed this with the SHOULD.

-Ben