Communities Plugin- How do you self-contain communities between each sub-site?

Communities plugin is almost exactly what I'm looking for but... it seems that the Communities plugin always shares all community plugin related data (internal messageboard posts, wiki's, comments, etc.) within the entire multisite itself, meaning any user on the entire multisite regardless of what sub-site they are apart of can view everyone else's information. It is not self contained on each "sub-site" of the multisite.

I need each sub-site Communities plugin features completely self contained- where no sub-site can see or find each others Communities data. How do I go about self-containing each sub-site's communities plugin information?

Also, the description of the plugin can lead one to believe that each sub-site will have an internal backend community with no shared data between every sub-site... Make self-containment an option of this plugin and no confusion or this question!