Re: [tsvwg] FW: [rmcat] Fwd: Submitted ID on delay vs. loss-only rate-adaptive for DiffServ

[James Polk <[e-mail]>]

At 08:36 AM 7/16/2013, Michael Ramalho (mramalho) wrote:
>TSVWG Members,
>
>I should have copied you on my email to the RMCAT mailer below.
>
>I strongly support the creation of a new DSCP for transports in 
>which their congestion control can adapt based on delay.
>
>The current ID in support of this 
>(http://www.ietf.org/internet-drafts/draft-polk-tsvwg-delay-vs-loss-ds-service-classes-00.txt 
>) is a work in progress, but a step in the right direction.

Michael

Thank you for the quick review.

The draft isn't very long (under 8 pages currently), and it is a work 
in progress - but do you have text or just points that this draft 
needs to cover that it doesn't currently?

James


>It is a given that the ability of the eventual RMCAT adaptation 
>mechanisms to achieve low delay will be function of the other 
>dominant traffic it is competing against. If the dominant competing 
>traffic DEPENDS on loss, the RMCAT packets are held hostage to being 
>delayed by the bottleneck queue delay maximum.
>
>Thus, whenever possible, it will be preferable for RMCAT flows to 
>compete with other congestion control transports that adapt on 
>delay. Even this may not get us to the desired low-delay goals when 
>a portion of the traffic has long RTTs (i.e., adaptation control 
>loops that are long in time), or for links that have a highly-time 
>varying capacity,  but it will help for a lot of common bottleneck 
>topologies (e.g., slowly time-varying access bufferbloat).
>
>It is my hope that this topic has some discussion time in the Berlin 
>Transport WG (not the specific codepoint to be chosen, but rather 
>the need for one).
>
>Off Soapbox,
>
>Michael Ramalho, Ph.D.
>
>-----Original Message-----
>From: Michael Ramalho (mramalho)
>Sent: Tuesday, July 16, 2013 9:06 AM
>To: [e-mail]
>Subject: RE: [rmcat] Fwd: [tsvwg] Submitted ID on delay vs. 
>loss-only rate-adaptive for DiffServ
>
>RMCAT Design Team,
>
>The draft Lars references below is a formal request for a DSCP 
>dedicated to "RMCAT-only (or other nice delay-based cc) traffic".
>
>It will take a while to become socialized ... and we can progress 
>our RMCAT work in the interim.
>
>Michael Ramalho
>
>-----Original Message-----
>From: [e-mail] [mailto:[e-mail]] On 
>Behalf Of Eggert, Lars
>Sent: Tuesday, July 16, 2013 5:26 AM
>To: WG WG
>Cc: [e-mail]
>Subject: [rmcat] Fwd: [tsvwg] Submitted ID on delay vs. loss-only 
>rate-adaptive for DiffServ
>
>Possibly of interest to RMCAT.
>
>Begin forwarded message:
>
> > From: James Polk <[e-mail]>
> > Subject: [tsvwg] Submitted ID on delay vs. loss-only 
> rate-adaptive for DiffServ
> > Date: July 16, 2013 8:07:59 GMT+02:00
> > To: <[e-mail]>
> >
> > (as an author)
> >
> > Toerless and I put together a draft about legacy rate-adaptation 
> based only on loss vs. what RMCAT is looking to (for RTCWEB), which 
> is based on delay and loss.  Here's the URL.
> >
> > 
> http://www.ietf.org/internet-drafts/draft-polk-tsvwg-delay-vs-loss-ds-service-classes-00.txt
> >
> > It's more raw than we had in mind, but we believe this is 
> necessary, based on implementation experience and what users and 
> customers have in their networks, or are planning on having in 
> their networks soon.
> >
> > James & Toerless
> >