SML to WSRC Mapping

Why WS-RC

WS-RC is intended to be used to define a structured description of resources located in some data repositories. It can provide metadata information about the resources (i.e. how to use them, what attributes) as well as how to locate them.

The part that becomes interesting from a COSMOS broker registry perspective is the resource metadata part. According to the WS-RC spec, we can use it to register information about an MDR and its data content. In CMDBf terms, a CMDBf administrator can use WS-RC to configure MDRs and federating CMDB to communicate with each other (describes what data can be exchanged, etc.).

How WS-RC relates with SML/CML/SDMX

• SML – no relation, SML is an XML language, while WS-RC is a specification based on XML. WS-RC may use SML to define its content but this is just speculation not worth investigating unless a clear usage is identified first.
• CML - the common model used to describe any type of resources. The only linkage I can see between CML and WS-RC is the fact that the catalogs defined using WS-RC are built upon a data storage which happens to contain resources in CML format. So there's not a lot of commonality between CML and WS-RC; CML is used to define resources, WS-RC is used to create a set of catalogs to access those resources.
• SDMX is used in COSMOS for the metadata registration part (i.e. define the keysets describing how to query a Data Manager). A WS-RC metadata registration technique can also be used to provide the same support.

Why not WS-RC

• The same support offered by WS-RC is currently available through SDMX; we have already invested in SDMX in COSMOS so a change to a new standard needs to provide at least some extra support or benefits, which are not clear at this point.
• WS-RC seems to be quite new; the spec refers to May 2007 so it seems that we don’t have yet a final polished version to work with.