Modeled entity instance requirements. A model entity instance (Node/Relationship Template) may represent an entity which has a dependency on its own realization (i.e. the version of the deployment artifacts used to materialize it at deployment time) and/or the existence of components with specific versions on which it depends. For example, SugarCRM may need to be deployed into a specific version of Apache web server along with version 5.3 of the PHP Runtime. Such dependency semantics are used by most modern language library managers (perl, ruby, ...) , package mangers (RPM, Deb, MSI, ...), and component containers (OSGI, PHP, process engines, ...).