Power consumption evaluation for next-generation passive optical networks

In this paper, we assess the energy efficiency of various optical access solutions including both the telecom operator and the end user side. We compare different next-generation passive optical networks (NG-PONs) to a baseline GPON deployment offering similar bandwidths and Quality of Service (QoS) for best-effort high speed connectivity services. For the operator side, we follow two approaches: first, we consider a fixed split ratio (1:64) in an existing optical distribution network (ODN); next, we consider an upgraded ODN with an optimized split ratio for specific bandwidth and QoS values. For medium bandwidth demands, our results show that legacy PONs can be upgraded to XG-PON without any ODN modification. For future applications that may require access rates up to 1 Gb/s, NG-PON2 technologies with higher split ratios and increased reach become more interesting systems, offering the potential for both increased energy efficiency and node consolidation. For the user side, we consider power consumption of the optical network unit (ONU), installed at the customer premises, incorporating several energy saving mechanisms. Combining our results for the central office and ONU side, we see that XLG-PON (using a bit-interleaving protocol) and TWDM-PON (using a standard protocol) consume the lowest power per user among the different NG-PON2 technology candidates.