Analysis of wavelength deployment schemes in terms of optical network unit cost and upstream transmission performance in NG-EPONs

Abstract

Next-generation Ethernet passive optical networks (NG-EPONs) were standardized by the IEEE 802.3 Working Group in 2020 [IEEE 802.3ca-2020–IEEE Standard for Ethernet Amendment 9: physical layer specifications and management parameters for 25 Gb/s and 50 Gb/s passive optical networks, 2020]. Due to the channel bonding technology [“Recent progress on 25G EPON and beyond,” in 42nd European Conference on Optical Communication (ECOC) (2016).] adopted by NG-EPONs, multiple wavelengths can be assigned to an optical network unit (ONU) simultaneously, leading to higher peak transmission rates. As a result, assigning traffic in multiple wavelength channels provides greater scheduling flexibility, a higher peak upstream rate, and better upstream transmission performance (i.e., lower latency); however, it leads to the use of high-cost ONUs with multiple transceivers and further increases the total cost of NG-EPONs. Therefore, selecting a proper wavelength deployment scheme is very important when designing future NG-EPONs. In this paper, we focus on the trade-off between ONU cost and the upstream performance in a static scenario, and we develop an integer linear programming model to formulate the problem. In addition, we propose a heuristic wavelength deployment scheme comparison and selection (WDSCS) algorithm to effectively select appropriate wavelength deployment schemes. According to our simulation results, our proposed WDSCS algorithm can efficiently find a finer number of deployment wavelengths to balance the cost of ONUs and the upstream transmission performance. The wavelength deployment schemes for future NG-EPONs can also be specified based on whether network operators prioritize network performance or cost.