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Re: [TLS] MTI policy & practice (Was: Re: Comments on various things on agenda)

Dave Garrett <davemgarrett@gmail.com> Mon, 09 March 2015 23:11 UTC

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From: Dave Garrett <davemgarrett@gmail.com>
To: Aaron Zauner <azet@azet.org>
Date: Mon, 09 Mar 2015 19:11:16 -0400
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Subject: Re: [TLS] MTI policy & practice (Was: Re: Comments on various things on agenda)
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On Monday, March 09, 2015 06:38:08 pm Aaron Zauner wrote:
> In any case, people do argue that algorithmic agility causes more
> problems than it's worth. I agree somewhat, but IMHO at least one
> backup is a good idea

I'd much rather have three than two. (not counting deprecated ciphers/modes) I think of it in this way: if one were to vanish, there would still be a choice left. With only two chosen ones, then a fatal attack on one brings us all the way back to the one-true-cipher again.

If you assume eventual failure, a secondary backup is very desirable.


Dave

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