Subject: [Trans] 6962-bis: Preventing Tracking Clients - follow-up

From: Eran Messeri <[email-masked]>
Date: Fri, 28 Sep 2018 15:26:15 +0100

Hi all,

I'm hoping to get WG consensus on whether we want the section about
"preventing tracking clients" in 6962-bis or not , particularly in light of
the recent document status change to "experimental" (Pending PR
<https://github.com/google/certificate-transparency-rfcs/pull/295>).

Those in favour of removing it suggested that it precludes the use of an
RSA mode that is otherwise recommended and that gossip is not yet defined
so it's premature to take it into consideration in a standards-track
document.

Those in favour of leaving it pointed out that building a gossip mechanism
without those properties would be very hard.

Personally I think this section should be left in since it will make
privacy-preserving auditing of logs ever harder than it currently is, there
are two methods for achieving that mentioned in the section (deterministic
signature schemes & caching of signed artefacts) and it is strongly
suggested (SHOULD), not mandated (MUST) - the way I see it it's a property
that the log generally should have as it would make auditing easier and
allow "STH discipline" but would not break the system if the log
occasionally produces duplicate signatures for the same STH / submission.

Regards,
Eran