A system-level software driver that is used by an EJB container or an application client to connect to an EIS. A resource adapter is typically specific to an EIS. It is available as a library and is used within the address space of the server or client using it. A resource adapter plugs in to a container. The application components deployed on the container then use the client API (exposed by adapter) or tool generated high-level abstractions to access the underlying EIS. The resource adapter and EJB container collaborate to provide the underlying mechanisms - transactions, security, and connection pooling - for connectivity to the EIS.