Connah Jessica J wrote:
I am currently working on a project looking at capturing networks in a tool agnostic way so that we can then easily migrate the networks onto different tools. I am interested in the outputs of your working group and what you decided was the best way to tackle this problem.
Hello Jessica, The working group has not reached the stage of integration with existing tools (in fact, it is only chartered to come up with a schema and syntax for network topology representation). A few software implementations are in the making, but as far as I know, those are all stand-alone. That said, most of the group members have encountered the same problem you are facing. Perhaps they can point you in the right direction. In particular, one of the earlier contributors developed the cNIS tool, which was designed with this interoperability problem in mind. cNIS was developed in the EU-funded GÉANT2 project. I can relate a bit about my experiences in this field. Originally coming from academy, our solution was to come up with a tool-agnostic network description, and build custom tools that import/export to that syntax. The network description we developed was NDL, and it was based on the ITU-T G.800 standard. G.800 provides building blocks to model networks in a technology independent way. The outcome of the NML working group will also be based on G.800, although some changes have been made, using the experience from other group members (NML is basically unidirectional, and there is a generic way to describe relations between the building blocks). One of the lessons we learned is that converting between syntax is easy, as long as the underlying model is the same. Using the G.800 building blocks and the NML schema (which, when finished, describes how to use those building blocks for particular technologies), there is a common model. Translating between syntax (e.g. in our working group there is voice to create a XML and a RDF syntax) is then relative simple. Four important choices for the model are (1) what identifiers to use for each component, (2) if the basis is unidirectional or bidirectional, (3) if the model is a single layer or a multi layer (cross-technology) description, (4) if the described network is single domain or multi-domain (thus often distributed and aggregated). The choices our group made where: (1) we use URI for all identifiers; (2) the basis is unidirectional (where bidirectional and broadcast are described using unidirectional -- a known limitation is that this does not work well for cellular networks); (3) we explicitly focus on multi-layer network, and how to relate the adaptation between the different technologies; (4) the working groups focus on the exchange of topology information between domain, and hence is multi-domain. Hope this helps a bit. Perhaps you could explain a bit about your particular problem. That may give a clue to other group members in your problem. Regards, Freek Dijkstra