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Re: [MLS] Unpredictable epochs?

Jon Callas <jon@callas.org> Fri, 26 April 2019 19:26 UTC

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From: Jon Callas <jon@callas.org>
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Date: Fri, 26 Apr 2019 15:26:54 -0400
Cc: Jon Callas <jon@callas.org>, Richard Barnes <rlb@ipv.sx>, Messaging Layer Security WG <mls@ietf.org>
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To: Michael Rosenberg <micro@fastmail.com>
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Subject: Re: [MLS] Unpredictable epochs?
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> On Apr 26, 2019, at 2:22 AM, Michael Rosenberg <micro@fastmail.com> wrote:
> 
> So why not remove epoch entirely?

An epoch lets you deal with things happening neither too often nor not often enough. Presume there is a client that is either malicious or just stupid. You want to keep it from forcing a rekey every 100µs. You want to force a rekey every so often. Hence epochs. Yeah, picking the right epoch size is an exercise left to the reader.

	Jon

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