Re: [TLS] draft-rescorla-tls-subcerts

Ilari Liusvaara <ilariliusvaara@welho.com> Fri, 15 July 2016 09:16 UTC

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Date: Fri, 15 Jul 2016 12:14:23 +0300
From: Ilari Liusvaara <ilariliusvaara@welho.com>
To: Andrei Popov <Andrei.Popov@microsoft.com>
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Subject: Re: [TLS] draft-rescorla-tls-subcerts
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On Fri, Jul 15, 2016 at 12:28:18AM +0000, Andrei Popov wrote:
> Naïve question: why not simply get a constrained CA certificate and
> issue short-validity end entity certs? Unless I’m missing something,
> this would work with existing TLS implementations, no extensions
> required.

The I-D actually covers this. Additionally, I think getting NC
certificate is quite expensive/difficult.

> Short-lived credential approach seems more viable than
> draft-mglt-lurk-tls-requirements-00 (which requires an additional
> round-trip between the Edge Server and Content Provider).

Those two serve different purposes. Sometimes you really need the
ES/KS split, sometimes short-lived certs would be more useful.


-Ilari