Re: [TLS] [Cfrg] (confusing the issues) Re: 3DES diediedie

Rene Struik <> Tue, 30 August 2016 01:32 UTC

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To: Jon Callas <>
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From: Rene Struik <>
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Date: Mon, 29 Aug 2016 21:31:47 -0400
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Cc: "David McGrew \(mcgrew\)" <>, "" <>, "<>" <>
Subject: Re: [TLS] [Cfrg] (confusing the issues) Re: 3DES diediedie
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My argument was aimed at focusing on the real topic at hand, not at 
mixing this with "religious" beliefs as ditching ciphers without clear 
justification (no matter how ancient 3-DES may be [I was in elementary 
school then]).

I think it is unwise thinking too lightly about writing IETF drafts with 
"die-die-die" in the title, just because one feels like it, in an almost 
context-free manner. Or, is the idea to launch an entire series of 
die-die-die drafts, because one finds some excuse to do so? I cannot 
deny I also like shiny new things and we may all suffer from 
not-invented-here syndromes, but acknowledging this playing in the 
background of our perceptions should also give us some reason to pause 
and have some restraint here.


On 8/29/2016 5:48 PM, Jon Callas wrote:
>> On Aug 29, 2016, at 6:26 AM, Rene Struik <> wrote:
>> I think it is a mistake to think that simply using block ciphers with a larger block size is enough to counter attacks, as the literature on successful side channel attacks on such block cipher demonstrates. The real message is that one should not reuse keys ad infinitum, which unfortunately seems hard to sink in.
>> Singling out 3-DES in this respect does not seem to tackle the real issue (which is a system security issue often only paid lip service to in practice).
> Yes, we should just stop using 64-bit block ciphers and deal with the issues you mention within the context of larger blocks.
> 	Jon

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