I am modeling a system that exposes a number of "plugins" (not known at modeling time) through a web API. I have a number of "system" plugins that permit to interact with the system, something like "list plugins", "describe plugins", "submit job (plugin execution)", "get job status", ... System and user plugins are exposed through either or both a JSON-RPC interface and WPS.
However I cannot figure out a component diagram depicting the fact that the same "logical" interface ("list plugins", ...) is exposed through physical interfaces (JSON-RPC and WPS). I would like to avoid replications and changing what is the standard description of the JSON-RPC and WPS interface. I feel this is something similar to the internet stack (e.g. TCP interface is built on top of IP interface), but I was not able to find diagrams of this.