Dynamic Bandwidth and Wavelength Allocation Scheme for Next-Generation Wavelength-Agile EPON

Abstract

Recently, the IEEE 802.3 Ethernet Working Group has classified three architectures for the nextgeneration Ethernet passive optical network (NG-EPON). They are called single-scheduling domain (SSD) PON, multi-scheduling domain (MSD) PON, and wavelength-agile (WA) PON, and they differ based on how a group of optical network units (ONUs) share a wavelength. Existing dynamic bandwidth and wavelength allocation (DBWA) schemes for conventional EPON can be applied to MSD-PON and SSD-PON, but not WA-PON. This is because WA-PON is a new architecture with full flexibility where a flexible number of wavelengths can be assigned to one ONU, and multiple ONUs can transmit at the same time. In this work, we develop a mathematical model and a novel DBWA scheme for transmission scheduling in WA-PON. However, as WA-PON incurs penalties in terms of delay and power consumption when an ONU activates its transmissions on new wavelengths, a trade-off between energy saving and data-transfer latency reduction needs to be carefully addressed when performing transmission scheduling. So, we develop a power-consumption model and modify the proposed DBWA scheme to enhance the energy efficiency of WA-PON. Finally, we conduct simulation experiments for performance evaluation of the three PON architectures in terms of latency and packet loss ratio. We quantitatively investigate the influence of various parameters, such as the number of ONU transceivers and ONU buffer size, on WA-PON latency and packet loss ratio, and we evaluate the energy efficiency gain of the modified DBWA scheme.

Unified Dynamic Bandwidth Allocation Scheme for Ethernet Passive Optical Network

“…Reference [22] dealt with the average packet delay and servicing frame sequencing issues to service DBA for EPON devices, particularly upstream wavelength channels. In [23], the authors developed a model and DBA scheme to schedule transmission with eradicated delays, and power consumption occurred when the ONU transmitted new wavelengths.…”

Wavelength-agile and radio-agile FiWi access network using dynamic scheduling to improve upstream delay and resource utilization

“…Using load of ONU and maximum permissible load at ONU, normalized load at each ONU will be evaluated. Now to implement scheduling on wavelength agile PON at backend, following issues need to be resolved: (1) How many wavelengths to be assigned to each ONU, (2) For what duration each wavelength need to be assigned, (3) How many ONUs will get single wavelength for transmission and (4) How the utilization of resources will be achieved while allocating wavelengths [8, 9]. In the proposed work at backend, multiple thresholds are generated depending upon the number of ONUs and load of ONUs.…”

“…WA-PON can use multiple wavelengths to transmit traffic to single ONU or a group of ONUs and simultaneously it can also take multiple ONUs traffics on single wavelength using time division multiple access (TDMA). WA-PON is considered to be the better approach for utilizing and scheduling bandwidth in PON [9]. Hence in the proposed architecture, WA-PON has been implemented at the backend of FiWi.…”

QoS-Based DWBA Algorithm for NG-EPON

“…In SSD-EPON, each ONU could transmit its traffic on all the channels simultaneously; hence, only one ONU can transmit its data at one time. Simultaneous transmission of data by multiple ONUs is not possible in SSD-EPON [15,16].…”