Re: [TLS] Testing consensus for adding curve25519 to the EC named curve registry

"Rob P Williams" <> Tue, 02 March 2010 15:20 UTC

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Date: Tue, 2 Mar 2010 10:20:55 -0500
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From: "Rob P Williams" <>
To: "Russ Housley" <>, <>
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Subject: Re: [TLS] Testing consensus for adding curve25519 to the EC named curve registry
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You don't need to involve IANA if you just follow RFC 4492...

Section 5.1.1:

      0xFF01 and 0xFF02 indicate that the client supports arbitrary
      prime and characteristic-2 curves, respectively (the curve
      parameters must be encoded explicitly in ECParameters).

-----Original Message-----
From: [] On Behalf Of
Russ Housley
Sent: Tuesday, March 02, 2010 9:59 AM
Subject: Re: [TLS] Testing consensus for adding curve25519 to the EC
named curve registry

I do not object to an additional code point being registered as long as
there is a document to explain how it works.  However, I also want to
understand the intellectual property issues, if any.  People have been
slow to adopt elliptic curve crypto due to intellectual property
concerns, which has prompted at least one document
( on the


On 3/1/2010 7:20 PM, Adam Langley wrote:
> We would like to start testing EC DHE in order to give our users
> forward-secrecy.
> In order to do this cheaply, one of the curves that we would like to
> test with is curve25519[1]. There are several implementations of it
> [2][3][4] and it's 3-4x faster than NIST's p256 (as implemented in
> OpenSSL), while being constant-time.
> Curve25519 doesn't currently appear on IANA's list of named curves[5]
> and we would like to see it included.
> As a first step I'd like to ask if there are any objections?
> Cheers
> [1]
> [2]
> [3]
> [4]
> [5]
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