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Re: [TLS] Data limit for GCM under a given key.

Dave Garrett <davemgarrett@gmail.com> Sat, 07 November 2015 04:21 UTC

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From: Dave Garrett <davemgarrett@gmail.com>
To: Eric Rescorla <ekr@rtfm.com>
Date: Fri, 06 Nov 2015 23:21:44 -0500
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Subject: Re: [TLS] Data limit for GCM under a given key.
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On Friday, November 06, 2015 10:54:02 pm Eric Rescorla wrote:
> I don't believe time-based guidance is useful here, given that it's highly
> situation specific rather than derived from reasoning about the properties
> of the cipher.

One reason to have a regular interval between rekeys is to ensure that it's a standard operation, rather than something implementations in many use-cases never see and possibly muck up when they eventually do. The time does not need to be short, though, and can vary by algorithm and implementation discretion.


Dave

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