Re: [TLS] I-D Action: draft-ietf-tls-prohibiting-rc4-01.txt

Stephen Farrell <stephen.farrell@cs.tcd.ie> Fri, 24 October 2014 10:43 UTC

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Date: Fri, 24 Oct 2014 11:43:42 +0100
From: Stephen Farrell <stephen.farrell@cs.tcd.ie>
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Subject: Re: [TLS] I-D Action: draft-ietf-tls-prohibiting-rc4-01.txt
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On 24/10/14 07:46, Salz, Rich wrote:
>> OS is a fine design pattern. Algorithms can be considered-good or
>> dodgy. AES is considered-good. RC4 is dodgy. OS requires 
>> considered-good algorithms (I think). With dodgy algorithms (esp.
>> with ciphertext-only attacks expected soon) OS is no better than
>> cleartext for confidentiality. So we ought say to not use RC4 when
>> following the OS design pattern.
> 
> There's a vocal minority(?) who strongly disagrees with this,
> particularly the last sentence.

Actually I think only Viktor and I have really gotten into
that part of the discussion. I mean about how OS and RC4
interact. Yes, there are others who'd prefer to go slower
deprecating RC4 or whatever, but their issues aren't related
to OS I think. (And just in case, OS here == Opportunistic
Security [1]).

S.

[1] https://tools.ietf.org/html/draft-dukhovni-opportunistic-security


> 
> -- Principal Security Engineer, Akamai Technologies IM:
> rsalz@jabber.me Twitter: RichSalz
> 
>