Active PCE demonstration performing elastic operations and hitless defragmentation in flexible grid optical networks. - Francesco Paolucci; Alberto Castro; Francesco Fresi; Muhammad Imran 004; Alessio Giorgetti; Bishanka Brata Bhownik; Gianluca Berrettini; Gianluca Meloni; Filippo Cugini; Luis Velasco 001; Luca Potì; Piero Castoldi (Photonic Netw. Commun., 2015)