Re: WGLC review of draft-ietf-quic-recovery-29

[Jana Iyengar <[e-mail]>]

There's a protocol question and there's a question of endpoint behavior. In
terms of the protocol itself, yes, there's no real need to distinguish
between Internet and DC environments; we've tried to ensure that the
protocol can be used broadly. My point was that the constants in the spec
were based on what we believe to be true for the public Internet, and not
for DC environments.

That said, perhaps I was a bit too hasty. IW10 and InitialRTT values are
the others I was thinking about, but those are recommendations in the spec,
not requirements. And as Ian notes, there's no minimum timeout anymore.

Perhaps we can have a principle here: recommendations that are specific for
Internet use are just that, and we use SHOULDs for those. IW10 makes sense
based on this, and I would then also be fine with changing the MUST to a
SHOULD. Perhaps we can state this principle upfront.

Ian, I share your hesitation that we don't want to make a distinction
between private and public networks, but we already allow for
implementations to do that with a different IW and Initial RTT. Is it
different when talking about burst limits?


On Fri, Jul 17, 2020 at 3:07 PM Jeremy Harris <[e-mail]> wrote:

> On 08/07/2020 22:29, Praveen Balasubramanian wrote:
> > Section 7.9
> > "Implementations MUST either use pacing or another method to limit such
> bursts to the initial congestion window; see Section 7.2."
> > This seems to preclude use of segmentation offload of sizes greater than
> IW.. In datacenters we routinely send bursts that are higher without
> causing loss. The MUST here seems unnecessary. It also conflicts with the
> RECOMMENDED in an earlier sentence.
>
> There's a way of satisfying both desires: have the NIC handle the
> pacing.
> --
> Cheers,
>   Jeremy
>
>