Proposal for IETF NETCONF Data Modeling Language Working Group

The IESG Secretary announced that a new IETF working group has been
proposed in the Operations and Management Area, described in a draft
NETMOD Charter. The NETCONF Working Group has completed a base protocol
to be used for configuration management. However, the NETCONF protocol
does not include a standard content layer. The specifications do not
include a modeling language or accompanying rules that can be used to
model the management information that is to be configured using NETCONF.
This has resulted in inconsistent syntax and interoperability problems.
The purpose of NETMOD is to support the ongoing development of IETF
and vendor-defined data models for NETCONF. The WG will define a
"human-friendly" modeling language defining the semantics of operational
data, configuration data, notifications, and operations. This language
will focus on readability and ease of use. This language must be able
to serve as the normative description of NETCONF data models. The WG
will use YANG as its starting point for this language. Language
abstractions that facilitate model extensibility and reuse have been
identified as a work area and will be considered as a work item or
may be integrated into the YANG document based on WG consensus. The
WG will define a canonical mapping of this language to NETCONF XML
instance documents, the on-the-wire format of YANG-defined XML content.
Only data models defined in YANG will have to adhere to this on-the-wire
format. In order to leverage existing XML tools for validating NETCONF
data in various contexts and also facilitate exchange of data models
SDL data modeling framework (ISO/IEC 19757) with additional annotations
to preserve semantics. The initial YANG mapping rules specifications
are expressly defined for NETCONF modeling. However, there may be
future areas of applicability beyond NETCONF, and the WG must provide
suitable language extensibility mechanisms to allow for such future
work. The NETMOD WG will only address modeling NETCONF devices and the
language extensibility mechanisms... Initial deliverables: (1) An
architecture document explaining the relationship between YANG and
its inputs and outputs; (2) The YANG data modeling language and
semantics; (3) Mapping rules of YANG to XML instance data in NETCONF;
(4) YIN, a semantically equivalent fully reversible mapping to an
XML-based syntax for YANG. YIN is simply the data model in an XML
syntax that can be manipulated using existing XML tools (e.g., XSLT);
(5) Mapping rules of YANG to DSDL data modeling framework (ISO/IEC 19757),
including annotations for DSDL to preserve top-level semantics during
translation; (6) A standard type library for use by YANG. The IESG
has not made any determination as yet; please send your comments to
the IESG mailing list by April 22, 2008.