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

Andrei Popov <Andrei.Popov@microsoft.com> Fri, 15 July 2016 17:34 UTC

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From: Andrei Popov <Andrei.Popov@microsoft.com>
To: "ilariliusvaara@welho.com" <ilariliusvaara@welho.com>
Thread-Topic: [TLS] draft-rescorla-tls-subcerts
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Cc: "tls@ietf.org" <tls@ietf.org>
Subject: Re: [TLS] draft-rescorla-tls-subcerts
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> The I-D actually covers this.
Understood; the I-D lists a few cons, but arguably none of them are blocking issues. It seems unnecessary to create a new TLS-specific mechanism that duplicates existing PKI semantics.

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

Cheers,

Andrei

-----Original Message-----
From: ilariliusvaara@welho.com [mailto:ilariliusvaara@welho.com] 
Sent: Friday, July 15, 2016 2:14 AM
To: Andrei Popov <Andrei.Popov@microsoft.com>;
Cc: Eric Rescorla <ekr@rtfm.com>;; tls@ietf.org
Subject: Re: [TLS] draft-rescorla-tls-subcerts

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