Re: [Bier] What is Slice Aggregate?

Toerless Eckert <> Tue, 09 November 2021 17:50 UTC

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Date: Tue, 09 Nov 2021 18:49:59 +0100
From: Toerless Eckert <>
To: Lizhenbin <>
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Subject: Re: [Bier] What is Slice Aggregate?
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I think a slice aggregate is a pizza

Sorry... to much serious IETF work, i just could not let that opportunity go,
but i am sure you could upsell the idea especially to the BIER-WG if you came
up with a way how the technology could be abbreviated PIZZA ;-)

Please carry on.


On Tue, Nov 09, 2021 at 01:34:47PM +0000, Lizhenbin wrote:
> Hi authors of draft-ietf-teas-ietf-network-slices,
> The authors of the draft draft-zzhang-bier-slicing-and-differentiation-00 mentioned in the draft:
> "
>    [I-D.bestbar-teas-ns-packet] introduces the notion of Slice Aggregate
>    which comprises of one of more IETF network slice traffic streams.  A
>    Slice Aggregate is identified by a Slice Selector (SS), and packets
>    carry the SS so that associated forwarding treatment or S-PHB (Slice
>    policy Per Hop Behavior - the externally observable forwarding
>    behavior applied to a specific packet belonging to a slice aggregate)
>    - can be applied along the path.
> "
> "
>    The authors of this document believe that the IETF Network Slicing
>    framework, when augmented by the Slice Aggregate, addresses the APN
>    problem domain very well.
> "
> According to the past discussion, we think the slice aggregate means the underlay slice, that is the new terminology "network resource partition".
> If so, the Slice Selector should be the identifier of the network resource partition. But according to the draft-zzhang-bier-slicing-and-differentiation-00,
> the slice aggregate can be augmented to address the APN problem. In the recently published draft draft-li-apn-header-00, the APN attribute is defined
> including the APN ID (user group/application group) the packet belongs to , the Intent and APN parameters applied to the packet. It is apparent these
> attributes are totally different from the identifier of the underlay slice.
> Can you clarify the following about the slice aggregate:
> 1. What is slice aggregate? Is it the underlay network slice, the APN attribute-like parameters, both or other identifier? Or can it be all possible identifiers to identify a flow?
> 2. What is the usage of the slice aggregate in the draft-ietf-teas-ietf-network-slices if it is not the network resource partition any more? Is it introduced a new identifier to identify a flow?
> 3. What is the scope of the slice aggregate work in the TEAS WG if it is a new identifier other than the resource partition? Will you go on to define the encapsulation and the
> protocol extensions for the new identifier or augment it to address the APN problem?
> Best Regards,
> Robin

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