[Netconf] with-defaults definition of 'explicit mode'

[Andy Bierman <andy at netconfcentral.com>]

Hi,

I don't think this definition of explicit defaults matches what
the NETMOD WG agreed to on the mailing list.

   o  Explicitly set default data: Is default data that is set by a
      NETCONF client or other external management application/user by
      the way of an actual management operation to the value specified
      as its default in the data model schema.  Some servers MAY treat
      explicitly set default data as simple default data, as they may
      not be able to differentiate between them.
      Data, that is set to a value other then its default value, is not
      default data, so its handling is outside the scope of this
      document.

IMO, this definition is too loose for the standard.
The NETMOD WG agreed that explicitly set means:
  o Explicitly set data:
    - any value set by the client
    - any value (other than the schema default) set by the server

The <with-defaults> leaf definition needs to match the
'explicit' retrieval mode.   The 'schema default' concepts
are not exactly the same as the 'explicitly set' concepts.

A system-created leaf is visible in all retrieval modes.
It MUST NOT be filtered out of an 'explicit' retrieval.
It would never be filtered by a 'trim' retrieval,
because s-c-stmt and default-stmt are incompatible.

There must not be any 'unclassified' data,
Every server MUST implement the 'explicit' mode the same way.
This goes for 'basic' behavior, not just the <with-defaults> leaf.


Andy