Re: [tcpm] Linux doesn’t implement RFC3465

Vidhi Goel <vidhi_goel@apple.com> Wed, 27 November 2019 01:11 UTC

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From: Vidhi Goel <vidhi_goel@apple.com>
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Date: Tue, 26 Nov 2019 17:11:01 -0800
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To: Lars Eggert <lars@eggert.org>, mallman@icir.org
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Subject: Re: [tcpm] =?utf-8?q?Linux_doesn=E2=80=99t_implement_RFC3465?=
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>> That is IMO the key question. *If* there is an alternative mechanism to ABC that solves (some of) the same problems, and potentially in a better way, or in a way that has a different implementation footprint, that may be worth documenting.

I think we can combine the byte counting mechanism of ABC for increasing congestion window and come up with an alternate way for controlling the burst sending. This will allow us to keep the two issues separate.

>> I'm not up to speed with the Linux code, but from what Neal writes, it seems that the Linux mechanism is tied in with or relying on a bunch of lower-level packet I/O functionality that is maybe pretty Linux-specific? In other words, can something like the Linux mechanism even be instantiated without (much of) this underpinning?

If we can come up with a generic approach (like pacing) to do it, an implementation wouldn’t require Linux specific mechanisms.

Vidhi

> On Nov 13, 2019, at 12:10 AM, Vidhi Goel <vidhi_goel@apple.com> wrote:
> 
> Adding Mark again as the bbn email doesn’t exist.
> 
> Vidhi
> 
>> On Nov 12, 2019, at 10:53 PM, Lars Eggert <lars@eggert.org> wrote:
>> 
>> Hi,
>> 
>>> On 2019-11-12, at 23:44, Vidhi Goel <vidhi_goel=40apple.com@dmarc.ietf.org> wrote:
>>> +Mark Allman
>> 
>> oh, is he at BBN now? Not mallman@icir.org?
>> 
>>> Is it worth investing time in writing another draft to document what Linux (and possibly other implementations) do for more accurate congestion window growth and for solving the burst send issue via pacing, TSQ etc.?
>> 
>> That is IMO the key question. *If* there is an alternative mechanism to ABC that solves (some of) the same problems, and potentially in a better way, or in a way that has a different implementation footprint, that may be worth documenting.
>> 
>> I'm not up to speed with the Linux code, but from what Neal writes, it seems that the Linux mechanism is tied in with or relying on a bunch of lower-level packet I/O functionality that is maybe pretty Linux-specific? In other words, can something like the Linux mechanism even be instantiated without (much of) this underpinning?
>> 
>> Lars