The Building Management System (BMS) is a complete and fully qualified stand-alone product for a single installation. In COMPOSITION, the BMS provides components for building local smart environments consisting of a number of devices, applications and services, which can be discovered and communicated with using the publish/subscribe or request/response messaging. The BMS device connectors provide integration of heterogenous devices in the middleware, implementing the functionality of the Device Integration Layer. Due to the diversity of available IoT devices and possible integration scenarios, it is a concept rather than a single component.
To see where the individual component belongs in the COMPOSITION Solutions, see the associated resource D2.4 The COMPOSITION Architecture Specification II.