Re: [tcpm] 2nd WGLC for draft-ietf-tcpm-rfc8312bis

[Yoshifumi Nishida <[e-mail]>]

Hi,
I just have one more comment on the draft.
In RFC5681, it mentions in Section 3:
''

   Implementation Note: An easy mistake to make is to simply use cwnd,
   rather than FlightSize, which in some implementations may
   incidentally increase well beyond rwnd.

"

while this draft mentions in Section 4.6:
"

   To avoid suboptimal performance with such applications,

   the mechanisms described in [RFC7661
<https://datatracker.ietf.org/doc/html/rfc7661>] can be used to
mitigate this
   issue as it would allow using a value between _cwnd_ and
   _flight_size_ to calculate the new _ssthresh_ in Figure 5.

"

So, it seems one PS doc mentions not to use cwnd, while another PS doc
mentions using cwnd is fine (with RFC7661).

I am not sure which can cause this situation yet, but in any case, does
this mean there is no concern on
"some implementations may incidentally increase well beyond rwnd" in cubic?
Is this because this is an old implementation bug or are there other
reasons?
I am wondering if we might want some clarification on this point.

Also, I am wondering if we might want to use "MAY be used" here instead of
"can be used"

Thanks,
--
Yoshi

On Mon, Jan 31, 2022 at 11:43 PM Yoshifumi Nishida <[e-mail]>
wrote:

> Hello,
>
> After some discussions among chairs, we decided to run the 2nd WGLC on
> draft-ietf-tcpm-rfc8312bis in consideration of the importance of the draft.
> We'll be grateful if you could send your feedback to the ML. The WGLC runs
> until *Feb 11*.
>
> If interested, you can check in-depth past discussions in the following
> URL.
> https://github.com/NTAP/rfc8312bis/
>
> Thank you so much!
> --
> tcpm co-chairs
>
>
> On Wed, Jan 26, 2022 at 2:50 AM Lars Eggert <[e-mail]> wrote:
>
>> Hi,
>>
>> this -06 version rolls in all the changes requested during (and after)
>> WGLC ended.
>>
>> I'll leave it up to the chairs to decide if another WGLC is warranted or
>> the document can progress as-is.
>>
>> Thanks,
>> Lars
>>
>>
>> > On 2022-1-26, at 11:12, [e-mail] wrote:
>> >
>> >
>> > A New Internet-Draft is available from the on-line Internet-Drafts
>> directories.
>> > This draft is a work item of the TCP Maintenance and Minor Extensions
>> WG of the IETF.
>> >
>> >        Title           : CUBIC for Fast and Long-Distance Networks
>> >        Authors         : Lisong Xu
>> >                          Sangtae Ha
>> >                          Injong Rhee
>> >                          Vidhi Goel
>> >                          Lars Eggert
>> >       Filename        : draft-ietf-tcpm-rfc8312bis-06.txt
>> >       Pages           : 35
>> >       Date            : 2022-01-26
>> >
>> > Abstract:
>> >   CUBIC is a standard TCP congestion control algorithm that uses a
>> >   cubic function instead of a linear congestion window increase
>> >   function to improve scalability and stability over fast and long-
>> >   distance networks.  CUBIC has been adopted as the default TCP
>> >   congestion control algorithm by the Linux, Windows, and Apple stacks.
>> >
>> >   This document updates the specification of CUBIC to include
>> >   algorithmic improvements based on these implementations and recent
>> >   academic work.  Based on the extensive deployment experience with
>> >   CUBIC, it also moves the specification to the Standards Track,
>> >   obsoleting RFC 8312.  This also requires updating RFC 5681, to allow
>> >   for CUBIC's occasionally more aggressive sending behavior.
>> >
>> >
>> > The IETF datatracker status page for this draft is:
>> > https://datatracker.ietf.org/doc/draft-ietf-tcpm-rfc8312bis/
>> >
>> > There is also an HTML version available at:
>> > https://www.ietf.org/archive/id/draft-ietf-tcpm-rfc8312bis-06.html
>> >
>> > A diff from the previous version is available at:
>> > https://www.ietf.org/rfcdiff?url2=draft-ietf-tcpm-rfc8312bis-06
>> >
>> >
>> > Internet-Drafts are also available by rsync at rsync.ietf.org:
>> :internet-drafts
>> >
>> >
>> > _______________________________________________
>> > tcpm mailing list
>> > [e-mail]
>> > https://www.ietf.org/mailman/listinfo/tcpm
>>
>> _______________________________________________
>> tcpm mailing list
>> [e-mail]
>> https://www.ietf.org/mailman/listinfo/tcpm
>>
>