Re: [Pce] new draft on segment routing approach to TSN

[Tianran Zhou <[e-mail]>]

Hi Yaakov,

This is an interesting topic.
After a quick review, there are several questions as follows:
1. It's clear to me to have a deadline for each packet. So that router can schedule the packet based on the urgency. But what's the motivation to split the end to end deadline to several local ones?
2. How to divide an end to end deadline into several local deadlines? Is there any example algorithm that could be used by the controller?
3. As far as I know, most devices do not support edf. I am not sure whether your proposal based on edf could really be useful.

Cheers,
Tianran


From: Pce [mailto:[e-mail]] On Behalf Of Yaakov Stein
Sent: Tuesday, February 23, 2021 9:14 PM
To: [e-mail]; [e-mail]; [e-mail]
Subject: [Pce] new draft on segment routing approach to TSN

All,

I would like to call your attention to a new ID https://www.ietf.org/archive/id/draft-stein-srtsn-00.txt
which describes using a stack-based approach (similar to segment routing) to time sensitive networking.
It furthermore proposes combining segment routing with this approach to TSN
resulting in a unified approach to forwarding and scheduling.

The draft is information at this point, since it discusses the concepts and does not yet pin down the precise formats.

Apologies for simultaneously sending to 3 lists,
but I am not sure which WG is the most appropriate for discussions of this topic.

  *   DetNet is most relevant since the whole point is to control end-to-end latency of a time-sensitive flow.
  *   Spring is also directly relevant due to the use of a stack in the header and the combined approach just mentioned.
  *   PCE is relevant to the case of a central server jointly computing an optimal path and local deadline stack.
I'll let the chairs decide where discussions should be held.

Y(J)S