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Re: [TLS] Consensus Call for acceptance of

Peter Gutmann <pgut001@cs.auckland.ac.nz> Wed, 25 June 2014 03:03 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: "<tls@ietf.org>" <tls@ietf.org>
Thread-Topic: [TLS] Consensus Call for acceptance of
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Date: Wed, 25 Jun 2014 03:03:25 +0000
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Subject: Re: [TLS] Consensus Call for acceptance of
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Watson Ladd <watsonbladd@gmail.com> writes:

>DHE without the extension is insecure.

Why?

(I know the abstract reason, but an unqualified "DHE without the extension is
insecure" is a bit like saying "ECDH is insecure", there is a situation where
it's insecure but it's pretty unlikely).

>Given the performance disadvantages of DHE compared with ECDH, I don't really
>see a benefit to supporting it, given that legacy implementations will not
>support this extension.

Legacy implementations won't support ECDH either, and adding a minor extension
to DH is easier and quicker than adding support for ECC.

Peter.

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