In this work, we provide a comprehensive comparison of various simplified coherent and direct detection (DD) schemes operating at a 100 Gb s 4-ary pulse amplitude modula- tion signal through numerical simulation. We review the current existing technologies, mainly in terms of the physical layer and higher media access control layer. These key. With the rapid advancements in coherent Passive Optical Network (PON) technologies featuring 100G and higher data rates, this paper addresses the urgent requirement for sophisticated simulation and MAC layer development within the domain of coherent Time Division Multiplexing (TDM) PON and coherent. Passive fiber TAPs now support SR4, LR4, and BiDi optics, deploy in sub-1RU chassis at high density, and integrate directly with packet broker platforms for intelligent traffic distribution. This. Ji Zhou, Jiale He, Xiaofeng Lu, Guanyu Wang, Yu Bo, Gengchen Liu, Yuanda Huang, Liangchuan Li, Chengkun Yang, Haide Wang, Wenxuan Mo, Weiping Liu, Changyuan Yu, and Zhaohui Li https://orcid. org/0000-0002-3185-0441 Your library or personal account may give you access To meet rapidly growing. In the rapidly evolving landscape of optical networking, the transition from 100GBASE-LR4 to 100GBASE-LR1 represents a significant technological milestone that is reshaping data center interconnections and telecommunications infrastructure worldwide. In essence, a PON is a fiber-optic system that delivers data from a single source to multiple endpoints using only.