Re: [Bloat] [Ecn-sane] [iccrg] Fwd: [tcpPrague] Implementation and experimentation of TCP Prague/L4S hackaton at IETF104

[Stephen Hemminger <stephen@networkplumber.org>]

On Wed, 20 Mar 2019 19:04:17 +0000
"Holland, Jake" <jholland@akamai.com> wrote:

> Hi Bob & Greg,
> 
> I agree there has been a reasonably open conversation about the L4S
> work, and thanks for all your efforts to make it so.
> 
> However, I think there's 2 senses in which "private" might be fair that
> I didn't see covered in your rebuttals (merging forks and including
> Greg's rebuttal by reference from here:
> https://lists.bufferbloat.net/pipermail/bloat/2019-March/009038.html )
> 
> Please note:
> I don't consider these senses of "private" a disqualifying argument
> against the use of L4S, though I do consider them costs that should be
> taken into account (and of course opinions may differ here).
> 
> With that said, I wondered whether either of you have any responses that
> speak to these points:
> 
> 
> 1. the L4S use of the ECT(1) codepoint can't be marked CE except by a
> patent-protected AQM scheduler.
> 
> I understand that l4s-id suggests the possibility of an alternate
> scheme.  However, comparing the MUSTs of the section 5 requirements
> with the claims made by the patent seems to leave no room for an
> alternate that would not infringe the patent claims, unless I'm missing
> something?
> 
> https://tools.ietf.org/html/draft-ietf-tsvwg-ecn-l4s-id-06#section-5
> https://patents.google.com/patent/US20170019343A1/en
> 

Has anyone done a detailed investigation for prior art?
The patent office does not do a good job of looking for prior art,
and the parties in the patent process are not motivated to look.

Other vendors often are not interested either because their own house of
cards built on patents of previous research might come falling down.