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

Peter Gutmann <pgut001@cs.auckland.ac.nz> Thu, 19 September 2013 09:56 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: "TLS@ietf.org (tls@ietf.org)" <tls@ietf.org>
Thread-Topic: [TLS] draft-sheffer-tls-bcp: DH recommendations
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Date: Thu, 19 Sep 2013 09:56:14 +0000
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Subject: Re: [TLS] draft-sheffer-tls-bcp: DH recommendations
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"Blumenthal, Uri - 0558 - MITLL" <uri@ll.mit.edu>; writes:

>I personally think that for *ephemeral* DH even 1024 bits still is enough.
>And would *much* prefer having PFS now with individual session keys at
>somewhat greater risk, over a system that is very secure and completely
>useless because nobody bothered to deploy it.

Exactly.  We don't need theoretically perfect security in ten years when we've
finished arguing about it and have upgraded every system on the planet to
support it, we just need good enough right now.  That's DH-1024, and when we
have that turned on everywhere we've got some breathing space to worry about
what to do next.

Peter.