The deliverable D3.3 Final security based discovery and composition mechanisms and tools of MUSA project has two components: the first is a working prototype that can be reviewed and evaluated online, while the second component is this document. This technical specification report describes the final prototype service discovery and composition software that is delivered as part of Work Package 3. This report details some of the discussions that led to change from the initial description of work and the innovation developed as part of this work package. Risk Assessment, Data Acquisition and Cloud Service Selection approach in MUSA are described in detail and references to the user guide (video) and repository of the accompanying software prototype are provided.