Обсуждение: Re: New CRC algorithm: Slicing by 8

Hi all,

    Michael Kounavis has given a green signal (please refer the forwarded message).

Best regards,

--
gurjeet[.singh]@EnterpriseDB.com
singh.gurjeet@{ gmail | hotmail | yahoo }.com


---------- Forwarded message ----------
From: Kounavis, Michael E <michael.e.kounavis@intel.com >
Date: Oct 20, 2006 10:43 PM
Subject: RE: CRC algorithm, Slicing By 8; concerns about patents infringements
To: Gurjeet Singh <singh.gurjeet@gmail.com>, Michael Kounavis < mekounav@users.sourceforge.net>

On Sun, Oct 22, 2006 at 08:10:56PM +0530, Gurjeet Singh wrote:
> Hi all,
>
>    Michael Kounavis has given a green signal (please refer the forwarded
> message).

I don't think that helps. The publishing date of this article was March
2006. If this is really the first time this algorithm was published, that
means that anyone else (or even the author) has the option of patenting
this algorithm sometime before March 2007 and still claiming they
invented it first.

And realistically we would wait at least a year or three after that,
because you don't get to see patents as they're applied for.

Maybe March 2010 we can look into it...

Have a nice day,
--
Martijn van Oosterhout   <kleptog@svana.org>   http://svana.org/kleptog/
> From each according to his ability. To each according to his ability to litigate.

On 10/22/06, Martijn van Oosterhout <kleptog@svana.org> wrote:
> On Sun, Oct 22, 2006 at 08:10:56PM +0530, Gurjeet Singh wrote:
> > Hi all,
> >
> >    Michael Kounavis has given a green signal (please refer the forwarded
> > message).
>
> I don't think that helps. The publishing date of this article was March
> 2006. If this is really the first time this algorithm was published, that
> means that anyone else (or even the author) has the option of patenting
> this algorithm sometime before March 2007 and still claiming they
> invented it first.
>
> And realistically we would wait at least a year or three after that,
> because you don't get to see patents as they're applied for.
>
> Maybe March 2010 we can look into it...

Consudering the author has OK-d it and given how easy
is to replace the algorithm, I don't see the reason for
such carefulness?

-- 
marko

On Sun, 2006-10-22 at 17:18 +0200, Martijn van Oosterhout wrote:
> On Sun, Oct 22, 2006 at 08:10:56PM +0530, Gurjeet Singh wrote:
> > Hi all,
> > 
> >    Michael Kounavis has given a green signal (please refer the forwarded
> > message).
> 
> I don't think that helps. The publishing date of this article was March
> 2006. If this is really the first time this algorithm was published, that
> means that anyone else (or even the author) has the option of patenting
> this algorithm sometime before March 2007 and still claiming they
> invented it first.

Slice-By-8 was first mentioned here:

M. E. Kounavis and F. L. Berry, "A Systematic Approach to Building High
Performance Software-based CRC Generators", Proceedings, Tenth IEEE
International Symposium on Computers and Communications (ISCC 2005), La
Manga Del Mar Menor, Spain, June, 2005.

so presumably the opportunity to patent has already passed, given what
you say.

> And realistically we would wait at least a year or three after that,
> because you don't get to see patents as they're applied for.
> 
> Maybe March 2010 we can look into it...

I think that's a tad overcooked. We have to balance caution with
boldness. Simply copying stuff from research can be dangerous, but I
think this is about as safe as it gets.

--  Simon Riggs              EnterpriseDB   http://www.enterprisedb.com

"Simon Riggs" <simon@2ndquadrant.com> writes:

> Slice-By-8 was first mentioned here:

Are you sure? 

US patent 7,047,479 filed in 2002 sounds like it may be relevant: 


http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=7047479.PN.

--  Gregory Stark EnterpriseDB          http://www.enterprisedb.com

On Mon, 2006-10-23 at 05:22 -0400, Gregory Stark wrote:
> "Simon Riggs" <simon@2ndquadrant.com> writes:
> 
> > Slice-By-8 was first mentioned here:
> 
> Are you sure? 
> 
> US patent 7,047,479 filed in 2002 sounds like it may be relevant: 
> 
>
http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=7047479.PN.

Yes, I'm sure.

That patent is titled "Parallel CRC formulation" and the abstract
describes the use of two threads to calculate different parts of the
CRC. It's designed for parallel circuit designs in hardware.

That doesn't resemble SB8 at all - there's still only one thread. The
cleverness of SB8 is to calculate more bytes simultaneously *without*
requiring a corresponding increase in the size of the lookup table. 

We have the original author's word that no patent has been filed. Even
if we disbelieve that, which I have no reason to do, that alone would be
sufficient to make a counter-claim for any damages claimed by any
hypothetical patent holder in the future.


What is the difference between this case and other patches?


--  Simon Riggs              EnterpriseDB   http://www.enterprisedb.com