[Nml-wg] NSI topology proposal

[Freek Dijkstra]

Hi Jerry and others,

Looking at your slide, I see two concepts, and I'm not sure if they're
the same or not.

The first concept is the hierarchical topology: describing a topology in
more and more (or less and less) detail.

The second concept is the alias: using a pointer to point from a generic
port or link ("the link between Nordunet and MAN LAN") to a more
concrete network element ("the link between Ciena 4000, intf 2/1 in
CPH001a and the Foundry 1234 intf 8/0 in NY002a").

Both concepts seem to deal with abstraction and can help distinguishing
between a _functional description_ of a network, and how those function
are _implemented_. However, the first concept is mostly about
aggregation, while the second is about versioning.

While I see aggregation as some "geographic" thing (how far do you zoom
in area), the version is a "time" thing (from when to when is this
conceptual link in place, and when is it ported to a different device).

I think NML can support either concept, but I wonder if we should
support both concepts, or if supporting one is good enough, or perhaps
both concepts are the same after all.

Regards,
Freek