Re: [TLS] Followup on Update
Martin Thomson <martin.thomson@gmail.com> Wed, 25 February 2015 03:45 UTC
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Date: Wed, 25 Feb 2015 16:45:05 +1300
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From: Martin Thomson <martin.thomson@gmail.com>
To: Eric Rescorla <ekr@rtfm.com>
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Subject: Re: [TLS] Followup on Update
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On 25 February 2015 at 15:00, Eric Rescorla <ekr@rtfm.com> wrote: > As a minor nit, it's kind of a pain to say every M minutes because > often TLS stacks are driven by the application and don't have internal > timers, but you could of course say "first record after M minutes" > which would (probably) be close enough. In addition to this, it seems like more of a policy decision that is driven more by circumstance than any direct security requirement. We might recommend that rekeying occur for long sessions, but it's hard to pick a one-size-fits-all value to recommend. As low as 10 minutes might be appropriate for high-value, high-volume data; whereas an IoT device with low-value, low-volume data might be content with rekeying only for the purposes of session extension (i.e., on a scale of days or weeks). As proposed, there is no significant security benefit to the Update protocol other than to stave off key exhaustion. I think that's a fine thing on its own merits, but I don't think we need to place too much weight on the mechanism.
- [TLS] Followup on Update Eric Rescorla
- Re: [TLS] Followup on Update Dave Garrett
- Re: [TLS] Followup on Update Eric Rescorla
- Re: [TLS] Followup on Update Martin Thomson
- Re: [TLS] Followup on Update Dave Garrett
- Re: [TLS] Followup on Update Ilari Liusvaara
- Re: [TLS] Followup on Update Watson Ladd
- Re: [TLS] Followup on Update Joseph Salowey
- Re: [TLS] Followup on Update Eric Rescorla
- Re: [TLS] Followup on Update Dave Garrett