Re: [Detnet] Packet Ordering Function (draft-varga-detnet-pof-00.txt)

Hi Ehsan,

Thanks for the comment. Right, “POFTakeAnyTime” has a special role.
It does not impact POF under normal circumstances. “POFTakeAnyTime”
allows to deal with some failure scenarios affecting the state of the POF
functionality. For example, when all paths of member flows fail for a while.

Cheers
Bala'zs

-----Original Message-----
From: Mohammadpour Ehsan <ehsan.mohammadpour=40epfl.ch@dmarc.ietf.org> 
Sent: Tuesday, April 20, 2021 12:02 PM
To: Balázs Varga A <balazs.a.varga@ericsson.com>
Cc: detnet@ietf.org
Subject: Re: [Detnet] Packet Ordering Function (draft-varga-detnet-pof-00.txt)

Hello Balàzs,

Thanks for starting a draft of POF. While reading the algorithm, I saw the parameter “POFTakeAnyTime”, where a received packet is forwarded  after no packet was received packet for the duration POFTakeAnyTime. 

I wonder about the need of this parameter. Can’t the POF function and algorithm work only with “POFMaxDelay”, since a packet is stored at the latest for POFMaxDelay? 
As written in the draft, POFTakeAnyTime must by larger than POFMaxDelay. Also at the POF point, it should incorporate the interspacing between the packets that might change significantly inside the network (comparing to source) due to the queuing delays and delay variations among the paths.

Best,
Ehsan

> On 20 Apr 2021, at 07:38, Balázs Varga A <balazs.a.varga=40ericsson.com@dmarc.ietf.org> wrote:
> 
> Hi,
> 
> A draft on Packet Ordering Function (POF) algorithms were uploaded.
> Comments and views are highly appreciated.
> 
> Thanks
> Bala'zs (and the authors)
> 
> -----Original Message-----
> From: internet-drafts@ietf.org <internet-drafts@ietf.org> 
> Sent: Tuesday, April 20, 2021 7:14 AM
> To: Balázs Varga A <balazs.a.varga@ericsson.com>; Janos Farkas <Janos.Farkas@ericsson.com>; Balázs Varga A <balazs.a.varga@ericsson.com>; Janos Farkas <Janos.Farkas@ericsson.com>; Stephan Kehrer <Stephan.Kehrer@belden.com>; Stephan Kehrer <stephan.kehrer@belden.com>; Tobias Heer <Tobias.Heer@belden.com>; Tobias Heer <tobias.heer@belden.com>
> Subject: New Version Notification for draft-varga-detnet-pof-00.txt
> 
> 
> A new version of I-D, draft-varga-detnet-pof-00.txt has been successfully submitted by =?utf-8?q?Bal=C3=A1zs_Varga?= and posted to the IETF repository.
> 
> Name:		draft-varga-detnet-pof
> Revision:	00
> Title:		Deterministic Networking (DetNet): Packet Ordering Function
> Document date:	2021-04-19
> Group:		Individual Submission
> Pages:		10
> URL:            https://www.ietf.org/archive/id/draft-varga-detnet-pof-00.txt
> Status:         https://datatracker.ietf.org/doc/draft-varga-detnet-pof/
> Htmlized:       https://datatracker.ietf.org/doc/html/draft-varga-detnet-pof
> Htmlized:       https://tools.ietf.org/html/draft-varga-detnet-pof-00
> 
> 
> Abstract:
>   Replication and Elimination functions of DetNet [RFC8655] may result
>   in out-of-order packets, which may not be acceptable for some time-
>   sensitive applications.  The Packet Ordering Function (POF) algorithm
>   described herein enables to restore the correct packet order when
>   replication and elimination functions are used in DetNet networks.
> 
> 
> 
> 
> Please note that it may take a couple of minutes from the time of submission until the htmlized version and diff are available at tools.ietf.org.
> 
> The IETF Secretariat
> 
> 
> _______________________________________________
> detnet mailing list
> detnet@ietf.org
> https://www.ietf.org/mailman/listinfo/detnet