Issue link: https://www.e-digitaleditions.com/i/1192126
12 I ICT TODAY when dark fiber is used or when critical services (e.g., healthcare) mandate the highest level of reliability. Standardization The number of optical transport options, including point- to-point (P2P) wavelength division multiplexing (WDM) and time and wavelength division multiplexing (TWDM) PON, as well as P2P WDM overlay, are important consider- ations for 5G and fixed wireless access too. Factors, such as capacity, latency support, cost, and reuse of the existing fiber infrastructure, are key in assessing the relevance of these options to 5G. Next-generation PON2 (NG-PON2) TWDM-enabled is already being discussed in the context of 5G. The need for guaranteed throughput, latency and reliability has led to the development of standards, includ- ing time-sensitive networking (TSN) and FlexE (or FlexEth- ernet) for 5G transport. The fronthaul-related specification of enhanced common public radio interface (eCPRI) and the requirement for scalable and higher bandwidth front/mid/back/cross-haul support with 100 Gb/s and 400 Gb/s Ethernet data rates being considered are some of the multiple facets of standardization. Focusing on the mobile transport domain, the push for open network architectures is manifested by the emer- gence of industry organizations and workgroups. The O-RAN Alliance and OpenRAN (part of the Telecom Infra Project), for example, are promoting open architectures and interfaces for virtualized radio access networks. Moving away from non-proprietary standards to simplify and optimize the use of fiber infrastructure is driving the requirements for next-generation transport. The sooner the relevant standards become finalized and mature, the better. In effect, fiber is needed to realize the benefits of C-RAN, NFV, SDN, MEC, and SBA. These concepts/technologies are critical pillars for 5G and future cloud-native networks. providers or enterprise/private networks as needed (i.e., in a more flexible manner than the model currently followed by mobile virtual network operators). These opportunities also highlight the importance of the underlying fiber infrastructure and the need to address all FiberG-related challenges. CHALLENGES FOR FiberG FiberG has a number of challenges to address, including: • High and low-level • New and old • Global and regional • Commercial and technical The advent of 5G has not made things easier. Investment Focus Practical challenges, such as digging when rolling out fiber, contribute to its overall rollout cost. In addition, the versatile nature of 5G further complicates the relevant decision-making and dimensioning processes. Operators must identify their use cases to target in the future how much additional fiber they should lay, perhaps to sup- port other operators as part of infrastructure sharing and to decide with whom they should be partnering including industry or local government. As part of their ROI focus, network operators should also be open to alternative options whenever a fiber roll- out appears to be challenging or altogether prohibitive. Regulation Regulation covers a variety of areas from the need to obtain permission for fiber installation/upgrades to the crucial role of fiber in 5G end-to-end network slicing. It will be interesting to see how SLAs for 5G services are monitored. It will also be intriguing to consider the regulations and possible penalties imposed in the case of degradation/outages if network slice performance is affected by fiber issues, as well as how fiber network operators will be regulated