[18908] in cryptography@c2.net mail archive
FW: How broad is the SPEKE patent.
daemon@ATHENA.MIT.EDU (Charlie Kaufman)
Thu Nov 10 18:03:40 2005
X-Original-To: cryptography@metzdowd.com
X-Original-To: cryptography@metzdowd.com
From: Charlie Kaufman <charliek@exchange.microsoft.com>
To: "cryptography@metzdowd.com" <cryptography@metzdowd.com>
Date: Thu, 10 Nov 2005 14:47:31 -0800
(resending after bounce)
-----Original Message-----
From: Charlie Kaufman=20
Sent: Wednesday, November 09, 2005 9:54 PM
To: 'Steven M. Bellovin'; James A. Donald
Cc: cypherpunks@jfet.org; cryptography@metzdowd.com
Subject: RE: How broad is the SPEKE patent.=20
----- Steven M. Bellovin wrote:
>Radia Perlman and Charlie Kaufman invented PDM specifically as a=20
>patent-free method. However, the claim was made that it infringed the=20
>SPEKE patent. Since it wasn't patented, there was no one willing to=20
>spend the money on legal fees to fight that claim, per a story I heard.
I am not aware that any claim (in the legal sense) has been made that PDM i=
nfringed SPEKE. Radia and I were pushing PDM in various standards bodies as=
a strong password protocol after convincing our employers not to patent it=
(no easy feat!). We were approached by David Jablon, the inventor of SPEKE=
but no longer the patent holder, who suggested that we should not assume t=
hat PDM did not infringe SPEKE and should not make such claims to others. T=
his was based on claims in a patent filed many years before but which throu=
gh various techniques had been prevented from issuing (a practice known as =
'submarining').
While we convinced our employers not to patent the protocol, we certainly w=
eren't going to get them to defend it.
That was sufficient to get us to stop promoting PDM. If anyone would like t=
o pick it up, they are of course free to do so. From a legal perspective, t=
hey would probably have a better chance with SRP, since Stanford holds a pa=
tent and might be motivated to support the challenge.
--Charlie
---------------------------------------------------------------------
The Cryptography Mailing List
Unsubscribe by sending "unsubscribe cryptography" to majordomo@metzdowd.com
