Affiliation: | 1.Hellenic Telecommunications Organization, Deutsche Telekom Group of Companies, 15122, Athens, Greece ;2.National Centre for Scientific Research “Demokritos”, 15310, Athens, Greece ;3.University of Huddersfield, Huddersfield, HD1 3DH, UK ;4.Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece ;5.International Technology University (ITU), San Francisco Bay Area, USA ; |