Re: [TLS] draft-sheffer-tls-bcp: DH recommendations

james hughes <hughejp@mac.com> Thu, 19 September 2013 06:10 UTC

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From: james hughes <hughejp@mac.com>
Date: Wed, 18 Sep 2013 22:54:26 -0700
To: "mrex@sap.com" <mrex@sap.com>
Cc: "tls@ietf.org" <tls@ietf.org>
Subject: Re: [TLS] draft-sheffer-tls-bcp: DH recommendations
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> On Sep 18, 2013, at 7:47 PM, mrex@sap.com (Martin Rex) wrote:
>> 
>> I'm not a cryptographer, but I'm actually not convinced that
>> counter modes of AES are a road I want to travel.  (I'm wondering:
>> do we actually know the length of the cycles of AES in counter mode?

Hmmm, I am, and, yes, we do. It is a well known proven fact that a properly chosen IV with a symmetric block cipher is full length, in that it is 2^128 blocks (for 128 bit AES) before recycling. I have a question for you... Do you have the patience to understand what "properly chosen" really means? 

This is a serious question.

I realize that there are a lot of politics within the TLS community that "real" cryptographers are not willing to play, and I may well be one of those whom you will wash away... 

Do you really want to hear, or are your own sound bites enough?