Re: [Trans] Prior knowledge of certificate serial number

Stephen Kent <> Thu, 25 September 2014 15:19 UTC

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Date: Thu, 25 Sep 2014 11:19:06 -0400
From: Stephen Kent <>
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Subject: Re: [Trans] Prior knowledge of certificate serial number
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> One of the questions that's come up is whether or not it's reasonable
> to expect that CAs will (or can) have knowledge of a certificate's
> serial number prior to issuance - it's one of the basic questions that
> needs to be considered in the context of the precertificate discussions.
> We'd be grateful if any CAs (particularly ones with a CT implementation
> either in the works or planned) could give some feedback on that.
I've expressed concern that many of the Web PKI CAs may not be
tracking the CT work. I suggest you contact someone at the CABF and
ask them to conduct a poll of their members. I propose two questions:

1. Is anyone from your organization tracking the IETF TRANS WG?

2. Would your (Web PKI) certificate issuance process be adversely
affected if you
- generated a TBScertificate, including all the fields normally present 
in certs you issue
- submit this TBScert structure to two or more third parties (over the 
- wait to receive a (newly-defined) extension value from each of these 
- insert the extension values into the cert and sign it, without 
changing any of the
cert fields in the TBScert from step 1