Subject: [nmrg] draft-clemm-nmrg-dist-intent-02

From: David Lenrow <[email-masked]>
Date: Thu, 1 Aug 2019 22:20:52 -0400

Hi all,
I really like the work that has been done in IRTF to capture intent work
and seek a clear, common definition. I hope I can jump into this
conversation and provide some thoughts.

As the chairman of the ONF NorthBound Interface (NBI) group at the time
that TR523 was published, I appreciate the comments in the draft stating
that results of the ONF work would be incorporated in future revisions. To
that end I think the primary thing that resulted from the work we did was a
recognition that it is not a complete fantasy (early resistance to intent
discussion) to have an (intent) policy that is completely independent of
implementation details. The way to do this is to have that policy reference
(dynamically updated) objects that are entirely implementation specific.
The value is not that complexity vanishes, but that the audience that
understands intent (sales team wants high-quality video conferencing
service) is different from the one that understands implementation (video
codecs, adaptive compression, multi-path forwarding, bandwidth utilization,
firewall rulees, etc.). Also, the latter set of concerns tend to be known
via machine-to-machine communications (message bus, distributed store,
etc.) in a way that ultimately lends itself to automation and autonomous
operation. It should be a real-time distributed database or messsage bus,
not a human administered entity built on /etc files :)

In summary, I think it is useful to define an intent based system as one
that strictly disallows implementation details in the “intent” part of the
desired state description, and also defines the mapping between the dynamic
objects referenced in policies, and the run-time, implementation specifics
of a given instance of such dynamic objects at a given point in time. The
opportunity and challenge is to build a system that separates the input of
intent from the delivery of real-time enforcement in a way that is easy to
use and understand.

My $0.02
-drl

David Lenrow
617 329 1861 (Rings all my phones).
@dlenrow