Re: [saag] A case against algorithm agility (long)

S Moonesamy <sm+ietf@elandsys.com> Mon, 05 May 2014 09:47 UTC

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Date: Mon, 05 May 2014 02:35:43 -0700
To: Andrey Jivsov <openpgp@brainhub.org>, saag@ietf.org
From: S Moonesamy <sm+ietf@elandsys.com>
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Subject: Re: [saag] A case against algorithm agility (long)
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Hi Andrey,
At 19:30 04-05-2014, Andrey Jivsov wrote:
>It is a good idea to limit the number of possible permutations of 
>allowed algorithms.
>
>However, the pros for the algorithm agility are:
>* compliance with standards (unless all standards in the world 
>specify the same suite)

There is an international industry standards group working on a 
reference architecture.  A draft which was published last month 
required compliance with a standard in which there is a security issue.

Is there a possibility that all standards in the world specify the 
same suite?  That sounds unlikely.  However, I looked at standards 
from two countries [1] and I found that they were referencing the 
same standard.

>* there might be no single algorithm that is perfect for everybody

Yes.

Every algorithm does not have to be standardized [2].  That can be a 
mechanism which implementations can use for other algorithms.

Regards,
S. Moonesamy

1. I took a quick look and I found more than two countries.  As I did 
not read the documentation I cannot say that there are more than two countries.

2. What the IETF considers as a standard.