Re: [TLS] TLS 1.3 - method to request uncached shared secrets

Dave Garrett <> Sat, 18 July 2015 18:28 UTC

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From: Dave Garrett <>
To: Brian Smith <>
Date: Sat, 18 Jul 2015 14:28:40 -0400
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Subject: Re: [TLS] TLS 1.3 - method to request uncached shared secrets
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On Saturday, July 18, 2015 01:06:33 am Brian Smith wrote:
> This is not really what I was intending when I suggested the feature. I was
> intending for their to be an indication, in the ClientHello, that the
> server should not do any of the work that it would normally do to make the
> session resumable.

Ok, I might as well write up the generic solution then:

This is an extension to allow a client to optionally request a specific session ticket lifetime. It can request a zero lifetime to disable session resumption and have the server not cache anything, request a max uint32 lifetime to request the maximum lifetime the server is willing to offer (up to the server if it wants to allow a longer lifetime than default), or request any specific lifetime (again, honoring is optional).

The extension is just a single uint32 value; including overhead, this is a total of 8 bytes.