A Learning-Automata-Based Congestion-Aware Scheme for Energy-Efficient Elastic Optical Networks

Abstract

The flexible nature of elastic optical networks (EONs) effectively uses spectral resources for optical communication by allocating the minimum required bandwidth to network connections. Since the energy consumption of such networks scales with the magnitude of bandwidth demand, addressing the issue of energy wastage is important. This fact has a profound impact on the design of efficient schemes for energy aware optical networks, and adaptivity arises as one of the most important properties of these networks. Learning Automata are Artificial Intelligence tools that have been used in networking algorithms, when adaptivity to the characteristics of the network environment can result in significantly improved network performance. In this work, a new adaptive power-aware algorithm is introduced, which selectively switches off bandwidth-variable optical transponders (BVTs) under low utilization conditions, to achieve energy efficiency. A novel adaptive scheme, which makes use of Learning Automata to significantly reduce the total energy consumption, while at the same time avoiding the onset of congestion, is proposed. The proposed scheme monitors network congestion, in terms of Bandwidth Blocking Probability (BBP), and the learning mechanism finds the optimal amount of energy-saving so that congestion is avoided, while at the same time significant energy savings are achieved. The proposed Learning Energy-Saving Algorithm (LESA) is evaluated via extensive simulation results, which indicate that it achieves an energy saving of up to 50%, compared to other energy efficient solutions.INDEX TERMS Adaptivity, elastic optical networks, energy-efficiency, learning automata, metropolitan networks.

Impact of Amplification and Regeneration Schemes on the Blocking Performance and Energy Consumption of Wide-Area Elastic Optical Networks

“…Here we assume that a regenerator is made of a variable bandwidth receiver and a transmitter in a back-to-back configuration. The model used to describe the electrical power consumption of a regenerator as a function of the bit rate [36], [37], [38] is as follows:…”

“…In this case K 1 and K 2 correspond to 1.683 W/Gb/s and 91.3 W, respectively [36], [37], [38], [39], [40], representing a power consumption of 260 W for a 100 Gb/s transmission. However, these values correspond to a study from 2010 [40].…”

Energy efficient optical backbone networks

“…In the results section provided in chapter 5 it is illustrated how affecting one of these two factors can influence the other. The research described in Chapter 5 has led to the works [10], [11], [12].…”

“…Power-aware heuristics, which selectively turn off network components under low utilisation conditions, during network operation, are presented in Chapter 5. The research described in Chapter 5 has led to the works [10], [11], [12]. Finally, chapter 6 concludes this thesis.…”

“…The data was indirectly derived from Cisco's 8-slot CRS-1 data sheets [12]. Each 8-slot CRS-1 chassis consumes about 8 kW of power, so on average each router port consumes about 1 kW of power.…”