Subject: [TLS] Robert Wilton's No Objection on draft-ietf-tls-external-psk-guidance-04: (with COMMENT)

From: Robert Wilton via Datatracker <[email-masked]>
Date: Wed, 15 Dec 2021 06:15:08 -0800

Robert Wilton has entered the following ballot position for
draft-ietf-tls-external-psk-guidance-04: No Objection

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COMMENT:
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Thanks for this document.  I find it always useful, and enlightening, when this
sort of guidance is published.

One minor nit/question on 7.  Privacy Considerations

   TLS does little to keep PSK identity
   information private.  For example, an adversary learns information
   about the external PSK or its identifier by virtue of it appearing in
   cleartext in a ClientHello.

I wasn't sure what "it" in the last sentence refers to.  I would potentially
read that as being the external PSK, and hence the external PSK appears in
cleartext in a ClientHello.  I don't know TLS, but this seemed surprising. 
Hence you may want to consider whether this sentence should be tweaked to make
it clearer.

Thanks,
Rob