Re: [TLS] Proto write-up for TLS exporter

[Simon Josefsson <simon at josefsson.org>]

Eric Rescorla <ekr at networkresonance.com> writes:

> At Wed, 13 May 2009 19:27:42 +0200,
> Simon Josefsson wrote:
>> 
>> Eric Rescorla <ekr at networkresonance.com> writes:
>> 
>> > Do you have some reason to believe that extractors itself is encumbered absent
>> > use of ECC?
>> 
>> Some of the patents quoted by Certicom in that PDF do not appear to be
>> specific to ECC.  There is no analysis that they don't apply to
>> tls-extractor.
>
> Again, the disclosure seems pretty clear to me. Namely,
> it states that the named documents apply "when used with...
> <three ECC-related documents>"
>
> So, again, I ask, "Do you have some reason to believe that extractors
> itself is encumbered absent use of ECC?"

I believe the PDF is a reason, at least without more information.  My
reasoning is as follows:

The patent disclaimer filed with the IETF lists tls-extractor as one
document that Certicom believes is covered by their patents.

The PDF only covers when ECC is used.

The PDF does not assert anything about non-ECC purposes.

This allows Certicom to claim that the tls-extractor document is covered
by their patents for non-ECC uses in the future.  That claim would not
be inconsistent with the information filed with the IETF so far.  That
is the loophole I'm concerned with.

My inclination is to be conservative about assuming the intentions of
patent holders without at least public statement to the contrary.

/Simon