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Re: [TLS] Removing the "hint" from the Session Ticket Lifetime hint

mrex@sap.com (Martin Rex) Mon, 29 February 2016 17:11 UTC

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To: "Salz, Rich" <rsalz@akamai.com>
Date: Mon, 29 Feb 2016 18:11:02 +0100
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From: mrex@sap.com
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Subject: Re: [TLS] Removing the "hint" from the Session Ticket Lifetime hint
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Salz, Rich wrote:
> Absolute lifetimes seem more robust; e.g., if you find one lying around,
> you don't have enough context to know if it's still good or not.
> 
> We went from relative to absolute times in ACME for this reason.

What should be memorized/stored is absolute time-of-creation.

How long to consider it valid, is a local issue and not necessarily
a constant validity period over time.  When memorizing time-of-creation,
you always know exactly how old something is, no matter whether how
many times the local validity period was changed in the meantime.

-Martin

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