The main objective of this work package is to federate the Brazilian and European sides of the testbeds taking part in this proposal. To this aim, WP4 will analyze the requirements, define the enhancements needed by the control frameworks involved, as well as adapt and deploy existing software suites. A federation architecture that is a strong candidate in FIBRE is SFA (Slice-based Federation Architecture) [18]. SFA has been successfully used in important projects, such as OneLab and is supported by the GENI initiative. Besides, many control frameworks are compatible with SFA, such as OMF [17] and OCF [19]. The SFA defines a web service interface that allows federation peers to exchange information and perform requests online. Each peer may implement its own privacy and policy constraints in the corresponding SFA layer through which private data can be hidden and failures can be returned if policies are violated. Some key features of SFA are authentication among federation peers/users and resource management. We will monitor and benefit from the best practices and solutions developed in frameworks such as FIRE and GENI. In addition, issues related to the physical interconnection of the various islands will be managed in this work package. Network Operation Centers (NOCs) will be established on both sides. RNP will maintain a national NOC on the Brazilian side, and will finance support at the participating universities with its own funds. i2CAT and University of Bristol are the potential candidates to provide the connectivity hub on the European side, maintaining each island its individual NOC and point of entry to the facility. The selection of the best choice for EU connectivity hub will be based on different factors such as cost and reliability. This decision will be taken when the actual integration is going to happen. The different solutions to bring all islands in the federation, from the architecture viewpoint, will be discussed so that the simplest operational solution will be followed. The need for a central NOC will be evaluated as part of this discussion.