Re: [Cellar] compression libraries in IETF specifications (was Re: [cellar-wg/matroska-specification] deprecate LZO compression (#376))

Adam Roach <adam@nostrum.com> Tue, 05 May 2020 21:18 UTC

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To: Spencer Dawkins at IETF <spencerdawkins.ietf@gmail.com>, Michael Richardson <mcr@sandelman.ca>
Cc: Codec Encoding for LossLess Archiving and Realtime transmission <cellar@ietf.org>
References: <cellar-wg/matroska-specification/issues/376@github.com> <24830.1588522227@localhost> <CAKKJt-dxwwWpOHweAFDOEnAvpOi5dnT1c8rtd-NwZYp-AU+Obg@mail.gmail.com>
From: Adam Roach <adam@nostrum.com>
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Date: Tue, 5 May 2020 16:18:29 -0500
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Subject: Re: [Cellar] compression libraries in IETF specifications (was Re: [cellar-wg/matroska-specification] deprecate LZO compression (#376))
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On 5/5/2020 3:43 PM, Spencer Dawkins at IETF wrote:
> Hi, Michael,
>
> On Sun, May 3, 2020 at 11:10 AM Michael Richardson <mcr@sandelman.ca 
> <mailto:mcr@sandelman.ca>> wrote:
>
>
>     Hi, I wanted to bring this item to the list's attention.
>
>     Spencer: I seem to remember that the IETF has had compression IPR
>     issues in
>     specifications in the past.  IPCOMP comes to mind, but I am
>     guessing that
>     other RTP/SIP groups have gone through this.. 
>
>
> I had forgotten IPCOMP, but was remembering RoHC and RoHCv2. I think 
> you're remembering SIGCOMP.


Probably not: SIGCOMP sidestepped this specific issue altogether by 
normatively specifying precisely zero compression algorithms. It instead 
defined a virtual machine that message recipients would implement, and 
to which message senders would send bytecodes sufficient to decode 
subsequent messages.

/a