[Teas] WG adoption of draft-king-teas-applicability-actn-slicing

[Adrian Farrel <[e-mail]>]

Hi TEAS,

As the debate over adoption of draft-nsdt-teas-transport-slice-definition
raging (I plan to pitch in on that soon), I wanted to remind the working
group about draft-king-teas-applicability-actn-slicing and ask the chairs if
they will consider that for adoption alongside the output of the Slicing
Design Team.

As you'll all be aware, ACTN is a key technology developed by this working
group that can be used for managing TE networks utilising many of the YANG
models developed in TEAS and elsewhere in the IETF. It closely follows SDN
architectures to provide a way for operators to provide services (and in
particular virtual network services) over their transport networks.

Enhanced VPNs (VPN+, also TEAS work) is about how basic VPN services can be
enhanced through the addition of service delivery objectives to represent a
service that turns out to look very much like network slicing.

It shouldn't be a surprise that ACTN is an appropriate tool for delivering
enhanced VPNs since they are a virtual network service.

What draft-king-teas-applicability-actn-slicing does is discuss the
applicability of ACTN to delivering network slicing services over TE
networks. It explains how you would build a slice, and it cross-references
the YANG models (in various states of development) that could provide the
information needed at the different interfaces.

While developing draft-king-teas-applicability-actn-slicing we obviously
needed to discuss terms and functions that are essential to an understanding
of network slicing. Some of these were borrowed from the enhanced VPN work,
which had previously borrowed them from an early version of this draft (what
comes around, goes around). It was not our intention to compete with the
Design Team work, but we needed this material in our document and we wrote a
lot of it way back in 2017 when we started the draft (somewhat before the
Design Team was formed).

There has been some debate about whether
draft-king-teas-applicability-actn-slicing is too limited because it can
only deliver slicing services over TE networks. That is a fine question, but
there is a strong argument that the act of slicing a network is only
possible through TE means whether those are implemented within the network
or in a centralised system. We might also ask whether TEAS is able to
address non-TE networks within its current charter.

If it turns out that there is WG preference for the terminology and language
used in the Design Team's documents then we would work out how to modify
draft-king-teas-applicability-actn-slicing. If, on the other hand, the WG
prefers the way we have expressed things then we would be please to see that
material find its way into a working group document. There would be two ways
to achieve that:
1. Leave it in draft-king-teas-applicability-actn-slicing and adopt that
draft
2. Modify the Design Team draft and reference it from
draft-king-teas-applicability-actn-slicing

Looking forward to your thoughts on this.

Best,
Adrian