Energy efficiency analysis with different modulation formats in elastic optical networks

The energy efficiency in telecommunication networks is gaining more relevance with the actual increasing traffic demand. In this paper, we compare the performance in terms of energy efficiency and blocking rate in elastic optical network (EON) for the NSFNET and USA topologies, by adopting three modulations formats: Binary Phase-Shift Keying (BPSK), Quadrature Phase-Shift Keying (QPSK) and Quadrature Amplitude Modulation (16QAM). An adaptation was made in the Routing algorithm Modulation Level and Spectrum Allocation (RMLSA) for the analysis of energy efficiency. The RMLSA adapted algorithm chooses the route with a modulation other than more robust or more complex, forcing the use of a modulation with intermediate energy efficiency. The obtained results showed that the RMLSA adapted algorithm obtained 1.1% higher and 38.5% lower energy efficiency, however 91.3% and 84.4% lower blocking rate when compared to Dijkstra and RMLSA algorithms for NSFNET topology, respectively. Additionally, it presented 1.11% higher and to 38.14% lowers energy efficiency, however 25.29% and 41.50% lower blocking rate when compared to Dijkstra and RMLSA algorithms on USA topology, respectively.