> From: Andy Bierman [mailto:abierman@cisco.com]
> Sent: Wednesday, June 09, 2004 11:42
> To: Frank Strauß
> Cc: netconf@ops.ietf.org
> Subject: Re: sub-tree filtering proposals
> IMO, we should do the following (yet another proposal :-)
>
> - mandatory-to-implement subtree node selection
Is the mandatory to implement based on what Jeurgen proposed?
> - optional-to-implement "full Xpath 1.0" node selection
> - #xpath capability set if this is supported
>
> The XML Directorate consensus seems to be leaning to partial
> Xpath, but there are strong concerns that an Xpath subset will be
> incompatible with standard tools, and therefore pointless.
It's not pointless. Some reasons that an XPath subset is useful are:
- compatability with full XPath which allows developers to learn one set of filtering
- code reuse between subset and full implementation
- training will be easier -- can leverage existing training for the bits we support
- a clean migration path from "XPath-lite" to "XPath-full"
>
> The advantages of the proposal above are:
> - subtree filtering is easy to implement on agents;
> only XML parser needed, not XML and Xpath parsers
> - subtree expressions are valid XML which look identical
> to the data models (XML content) that operators will
> need to know anyways. Xpath should not be mandatory-to-know
> in order to use NETCONF.
> - Vendors are encouraged to also support full Xpath 1.0, if it
> is appropriate for the platform and data model size
> - We avoid definition and deployment of a NETCONF-only Xpath subset
>
> Andy
Regards, /gww