Re: [tcpm] [tsvwg] Cross-area alignment on "L4S and RACK"

["Black, David" <[e-mail]>]

> As far as I understand, the DETNET WG in RTG area has quite some uses cases for ultra-low latency transport - in particular also with bounded jitter.
> And some of these applications (e.g. using UDP) apparently may not be able to tolerate *any* out-of-order packet delivery.

I’m the Transport Technical Advisor to the DETNET WG – the envisioned DETNET data path structure is similar to Intserv or policy-based routing- a full 5-tuple match (2 x addr, protocol 2 x port) on all inbound traffic picks off the flows that requires deterministic forwarding and diverts them into a DETNET data path that maintains per-flow state before the Diffserv logic looks at the DSCP or L4S logic  looks at ECT(1) to figure out what to do with the (non-deterministic) rest of the traffic which is handled as flow aggregates (no per-flow state in forwarding path).

This could be made clearer in their drafts …

Thanks, --David

From: tsvwg [mailto:[e-mail]] On Behalf Of Spencer Dawkins at IETF
Sent: Tuesday, November 6, 2018 5:14 PM
To: [e-mail]
Cc: tcpm IETF list; [e-mail]
Subject: Re: [tsvwg] Cross-area alignment on "L4S and RACK"


[EXTERNAL EMAIL]
Please report any suspicious attachments, links, or requests for sensitive information.
Michael,

On Wed, Nov 7, 2018 at 2:20 AM Scharf, Michael <[e-mail]<mailto:[e-mail]>> wrote:
A comment on the TCPM presentation "L4S and RACK":

As far as I understand, the DETNET WG in RTG area has quite some uses cases for ultra-low latency transport - in particular also with bounded jitter. And some of these applications (e.g. using UDP) apparently may not be able to tolerate *any* out-of-order packet delivery.

So perhaps some cross-area alignment on ulta-low-latency application requirements would be useful?

Michael
(who recently had to review draft-ietf-detnet-architecture)

I'm not a responsible AD for DETNET, but we approved https://datatracker.ietf.org/doc/draft-ietf-detnet-use-cases/ within the last couple of weeks.

My understanding is that at least some of the use cases have that intolerance for out-of-order delivery (among other characteristics). That was certainly the case when we chartered DETNET.

I'm sure TSV will do the right thing ;-)

Spencer