Hi - > From: "Dave Crocker" <dhc2@xxxxxxxxxxxx> > To: "Eric Rescorla" <ekr@xxxxxxxxxxxxxxxxxxxx> > Cc: <iesg@xxxxxxxx>; <ietf@xxxxxxxx> > Sent: Tuesday, April 22, 2008 10:03 PM > Subject: Re: WG Review: NETCONF Data Modeling Language (netmod) ... > Are they committed to doing the work? The bulk of the work has been done (or close to it) for quite some time. Ideally, it would have been done *before* the NETCONF protocol was cast in concrete, but the NETCONF working group was not allowed to define a modeling approach before finishing a protocol. Without data models, the protocol is useless. Consequently, there are already numerous vendor-specific ways of handling modeling, and even multiple approaches showing up some companies. Not good. > Do they have their own constituency? All the major players in the devlopment of the NETCONF protocol, as far as I know. > Since the topic is not new, where have they been and why have they not > developed their own group consensus? Previous requests for a BOF like the one held in Philadelphia were denied. The various design teams have considerable common ground, and the consensus of the folks who are actually doing work is in my opinion pretty accurately reflected in the charter proposal. > Rather than "perspectives" where are the technical concerns that Bert asked about? As I see it, the key technical issues are these: 1) Is there a need for a domain-specific language for network configuration management data modeling? Experience in the field gives an unequivocal "yes". GDMO, SMI, and CIM are a few examples of how folks have dealt with the shortcomings of the general-purpose tools available over the years. General-purpose modeling languages are both too much and too little, particularly with regard to issues of inter-version compatibility of models and interoperability. Even if a language can represent an important semantic, there's still the question of whether that particular solution is compact and intuitive. With some, to represent common constraints like uniqueness the designer had to resort to the equivalent of assembler language. 2) Does it make sense to use an XML-based syntax for the "human-friendly" representation of data models? For "industrial-strength" models the answer becomes more and more "no" as the model becomes larger and more semantically rich. This is not a question of expressive power. It's a question of providing a way to support development of *readable* standardized data models for NETCONF. Forgive my impatience. We went through this same debate twenty years ago regarding ASN.1 and GDMO, and only slightly later in de-coupling SNMP SMI from ASN.1 The acronyms may have changed, but the answers haven't. Randy _______________________________________________ IETF mailing list IETF@xxxxxxxx https://www.ietf.org/mailman/listinfo/ietf