Re: [tcpm] Curiosity about draft-mathis-tcp-ratehalving

["Scheffenegger, Richard" <rs at netapp.com>]

Hello Carsten,

This is a very good question indeed.

Keeping the ACK clock running, and avoiding bursts of segments delivered
all at once in a single burst to a L2 LAN network is something
where my interests are too... (as todays hosts are increasingly capable
of oversaturating slightly dated network equipment with full wire speed
traffic).

Is there a procedure to revive / adopt a dead draft?

I have not spent much time on this issue, but noted the burst behavior
After fastretransmit.


As RateHalving extended the scope of Limited Transmit (with the similar
goal), shouldn't this be discussed for inclusion in a RFC 3042bis?

Since certain other congestion algorithms have a beta of less than 0.5 
(ie. BIC, CUBIC use 0.8) when selecting a new ssthresh, perhaps the
effect
of RateHalfing, but with 2 out of 3 (0.66) policy or 3 out of 4 (0.75)
at the end of the RTT should be investigated? (To be less conservative
When reducing the sending rate).

One extension to the draft might be the discussion on how to deal with
RFC 3465 (ABC) during rate halving; with SACK, ABC could still be
employed,
And a new segment triggered only, when 2*MSS has been covered by the new
SACKs...

Regards,

Richard Scheffenegger
Field Escalation Engineer
NetApp Global Support 
NetApp
+43 1 3676811 3146 Office (2143 3146 - internal)
+43 676 654 3146 Mobile
www.netapp.com <BLOCKED::http://www.netapp.com/>  
Franz-Klein-Gasse 5
1190 Wien 

*	To: Matt Mathis <mathis at psc.edu <mailto:mathis at DOMAIN.HIDDEN>
>
*	Subject: [tcpm] Curiosity about draft-mathis-tcp-ratehalving
*	From: Carsten Wolff <carsten.wolff at rwth-aachen.de
<mailto:carsten.wolff at DOMAIN.HIDDEN> >
*	Date: Wed, 4 Nov 2009 13:48:51 +0100
  _____  

Hello Matt, everyone,

I'm curious about draft-mathis-tcp-ratehalving 
(http://tools.ietf.org/id/draft-mathis-tcp-ratehalving-00.txt) and why
it 
never exceeded version 00 and expired years ago. It seems, several of
the 
ideas (fack, ratehalving, the concept of rhcwnd) in this paper made it
into 
the Linux TCP implementation in some form, which means they're part of a
big 
chunk of today's web servers and other Internet hosts. Why has there
been no 
interest in taking this draft further?

Cheers,
Carsten