Re: [netmod] Does defining a feature require the module be implemented?

Kent Watsen <> Sat, 04 June 2022 20:57 UTC

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From: Kent Watsen <>
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Date: Sat, 04 Jun 2022 20:57:44 +0000
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Cc: Martin Björklund <>, "" <>
To: Robert Varga <>
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Subject: Re: [netmod] Does defining a feature require the module be implemented?
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Hi Robert,

>> 3) I wish more modules would following the pattern of having the global protocol accessible tree be defined via a "uses" of a grouping defined in the module.   In another recent project, I had to hack the topology modules defined in RFC 8345 (to convert the containers to groupings) to enable a multiplicity of "abstract network topologies" to be configured.   The assumption that only a single global instance is ever needed is proving to be invalid in my work time and again.
> /me puts the co-author hat on.
> The multiplicity is already built-in into the model by the fact that network topologies is a top-level list.
> Would you mind sharing the use case what requires multiplicity of the built-in multiplicity?
> I know this sort-of is a re-hash of the ietf-interfaces discussion, but while there the use-case is well understood, I wonder what equivalent is there for networks/topologies.

I appreciate that the model supports a multiplicity of topologies, and can see that it could support my needs, but my issue seems to arise in the intersection of the following desires:

	1) a server that supports multi-tenancy
	2) each tenant being able to define a number of topologies
	3) each tenant only being able to see their own topologies
	4) the server not supporting object-level access control
	5) the data-model being schema-mount like, whereby each tenant-instance contains *all* tenant nodes (e.g., all leafrefs are relative paths that never go above the tenant's subtree.