TUCAN3G aims to develop solutions to provide 3G services in isolated rural areas of developing countries. In order to do so, this document starts by analysing the reference scenarios where TUCAN3G solutions could be applied, explaining its general situation worldwide, the Latin America case, and its specific reality in Colombia and Peru, from the socioeconomic point of view. The technologies that TUCAN3G will integrate for this purpose are also described, providing an insight of the requirements that should be provided and the methodologies that will be used for both, the access and the transport network. Based on the former analysis, a design for the demonstration platform is performed, including a proposal for target localities, a general description of test to be carried out, and the needs of existing networks.