This thesis is a contribution to the federation of asynchronous SmartSantander service layer within the European Fed4FIRE context. The thesis was developed in a Smart City background, and its main aims were both to gain knowledge of how Smart Cities, Testbeds and Federations of Testbeds are structured by working on a real deployed system, i.e. SmartSantander framework and Fed4FIRE federation, and to contribute with some of the components required for the integratio