[Cryptography] Large companies sued for using Elliptic Curve TLS?

Jerry Leichter leichter at lrw.com
Tue Dec 1 16:40:57 EST 2015

> A Certificate does not offer “proof" that the “public key was generated properly”. It proves the identity of the public key. Unless they are not using a normal term for “proof” and/or “properly", I find this hard to believe that an EC public key can be “proven” that it was generated properly. 
You're reaching conclusions based on quotes of quotes of text from a patent - and patents are hardly the best places to learn how any complex technology actually works.  Nevertheless, this patent seems to have a detailed explanation of the underlying math.  (I haven't gone through it in detail.)

Both authors have done a great deal of work in cryptography.  Both in particular have worked on "kleptography" - techniques for "spiking" various cryptographic algorithms in undetectable ways.  This work is actually a variation on a theme:  The generated public keys leak information to a suitably-informed third party, while being secure against anyone else - as is generally the case in kleptography.  The difference is that in this case the leakage is an open and desired (by all participants) property of the system.

It also seems clear - to me, anyway - that the details of what the patent claims do not cover any normal use of ECC.  But we may actually never know, because as pointed out in "allenpmd"'s message earlier today, Netflix is attacking the patent on procedural/technical deficiencies in the way it was drafted, and if they prevail - which on the surface seems likely - the patent will be tossed without anyone ever examining what it actually means or covers.)
                                                        -- Jerry

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