From owner-freebsd-isdn  Fri Oct 26  7:30:57 2001
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Date: Fri, 26 Oct 2001 15:30:53 +0100 (BST)
From: Andrew Gordon <arg-bsd@arg1.demon.co.uk>
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To: Poul-Henning Kamp <phk@critter.freebsd.dk>
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Subject: Re: RFC1974 (STAC) 
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On Fri, 26 Oct 2001, Poul-Henning Kamp wrote:

> In message <20011026132510.N36971-100000@server.arg.sj.co.uk>, Andrew Gordon wr
> ites:
>
> >However, STAC holds patents on the compression algorithm, so the legal
> >status of any implementation would be questionable.
>
> Do they only hold compression or also decompression patents ?

All the ones I can find seem to describe the compression process only:

http://www.delphion.com/details?pn=US05506580__
http://www.delphion.com/details?pn=US05532694__
http://www.delphion.com/details?pn=US05463390__
http://www.delphion.com/details?pn=US05414425__
http://www.delphion.com/details?pn=US05146221__
http://www.delphion.com/details?pn=US05126739__
http://www.delphion.com/details?pn=US05016009__
http://www.delphion.com/details?pn=US05003307__

so an implementation that implements decompression only (using
non-compressed PPP packets on the transmit side) would seem to be OK.

It's rather a narrow loophole though!

> >It is also not clear that it offers much advantage in typical use, since
> >....
>
> STAC makes a good dent in the tcp headers and stuff...

Even after they've been VJ-compressed?


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