OS4ES System Architecture, component requirements and communication infrastructure - C. v. d. Broek and Antonis Papanikolaou and Mikel Fernandez and J. Merino and Stjephan Sucic and Tim Dethlefs and Andrea Pawils and Christoph Brunner and D. Papapolyzos and E. Hatzoplaki and C. Malavazos and D. Grammatikos and Wolfgang Renz and Jörg Benze (The Open System for Energy Service Project (OSES), 2015)