Re: [Dyncast] Updates on Dyncast drafts

Aijun Wang <> Sat, 20 February 2021 02:42 UTC

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From: "Aijun Wang" <>
To: "'Dirk Trossen'" <>, <>
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Date: Sat, 20 Feb 2021 10:42:21 +0800
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Subject: Re: [Dyncast] Updates on Dyncast drafts
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Hi, Dirk:


I have a quick review of the usecase and architecture draft that you
provides and think this is one interesting topic to discuss within IETF.

Regarding to the usecase draft, as I known, there are also other SDO(ITU
etc.) studying on this topic, can anyone share what their progress now and
can we refer to their work to prove the necessary of such service needed in
the network?

Regarding to the architecture draft, I am litter confusion about two mapping
components as described in section 5. " Dyncast Control-plane vs Data-plane

1.     Why we need the mapping of (D-SID, D-BID)?  

We are mentioning "Dynamic Anycast" architecture, why don't' use just one
unique D-SID in several locations for one service?  The router have the
capabilities to select what's the most optimal path to reach the service
that identified by D-SID.


2.     Why we need the mapping between D-Router and D-Forwarder?

It seems not easy to introduces the D-Forwarder entity into the network,
also the mapping between them. I think we should first focus on utilizing
the existing network devices to accomplish the aim.


The answers to your questions are inline below [WAJ].


Best Regards


Aijun Wang

China Telecom




From: <> On Behalf Of Dirk
Sent: Tuesday, February 16, 2021 1:18 AM
Subject: [Dyncast] Updates on Dyncast drafts


Dear All,


For the preparation to the planned side meeting at the upcoming IETF110
(more details on this will follow in a separate email), it is our intention
to formulate use cases, problems and architectural requirements for
addressing those problems in order to focus this side meeting on the
following two main questions:

1.       Are the use cases compelling and the problems worth to be discussed
and possibly solved in the routing area?

[WAJ] Yes, I think it is possibly solved in the routing area.


2.       What would be the best approach in doing so within the IETF, e.g.,
through a new WG focusing on dyncast or through contributions to existing,
protocol-specific WGs, with problem and requirements kept as contributions
to the RTG WG?

        [WAJ] Based on current information about the use case and the aim, I
think contributions to existing, protocol-specific WGs is feasible.


Depending on what the community thinks, we will go for a more formal meeting
at IETF111. 


As input material for our discussion, we have uploaded the following three
Dyncast drafts to the datatracker, namely the Dyncast use case and problem
statement at and the
Dyncast requirements at We have also
uploaded a draft outlining a possible Dyncast architecture at


Any comments or views on either of those two questions above are warmly
welcome in preparation to the planned side meeting. We hope to see many of
you there.





Dirk (on hehalf of the authors of the Dyncast drafts)