Re: [Trans] Precertificate format

Brian Smith <> Tue, 09 September 2014 20:15 UTC

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Date: Tue, 9 Sep 2014 13:15:22 -0700
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From: Brian Smith <>
To: Rob Stradling <>
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Cc: Melinda Shore <>, "" <>
Subject: Re: [Trans] Precertificate format
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On Tue, Sep 9, 2014 at 3:17 AM, Rob Stradling <> wrote:
> I don't mind us adding an alternative Precertificate format to 6962-bis (if
> we can agree on a suitable format!), but I'd also like to retain the RFC6962
> Precertificate format as an option.

If the old form is acceptable, then there would be no point in
defining a new form. The chief issue is that technically the old form
of precertificate is technically a certificate, and since it has the
same issuer name it must (according to RFC 5280) have a different
serial number. It would be good for the group to decide whether or not
that issue is so bad that we cannot accept it. If it is that bad, it
makes sense to define a replacement format. If it isn't so bad that we
can't accept it, then it doesn't make sense to define a replacement
format, IMO.

> Several CAs have already deployed code to generate RFC6962 Precertificates.
> Why force these CAs to change to a different format just because some other
> CAs find it hard to implement the RFC6962 format?

If the only issue is whether it is a little bit tricky to implement
the X.509-certificate form of precertificate, then there's no point in
defining a new format. CAs always have the non-precertificate
mechanism to fall back on.

IMO, the ultimate goal should be to get the non-precertificate
mechanisms working well enough that we can remove (or at least
deprecate) the precertificate mechanism completely.