NG-PONs 1&2 and beyond: the dawn of the uber-FiWi network

This article reviews the main thrusts in next-generation passive optical network 1 and 2 technologies that enable short-term evolutionary and long-term revolutionary upgrades of coexistent gigabit-class PONs, respectively. It provides insight into the key requirements and challenges of the major candidate NG-PON 1&2 architectures such as long-reach XG-PON, wavelength-routing WDM PON, OCDMA and OFDMA PON, and reports on recent progress toward enhanced data and control plane functionalities, including real-time dynamic bandwidth allocation, improved privacy and guaranteed QoS, bandwidth flexibility, as well as cost-effective in-service monitoring techniques for NG-PONs. We then elaborate on converged optical fiber-wireless access networks, which may be viewed as the endgame of broadband access, and explain the inherent coverage and QoS issues of conventional radio-over-fiber networks for distributed wireless MAC protocols and how their limitations can be avoided in so-called radio-and-fiber networks. We explore powerful layer-2 optical-wireless, hierarchical frame aggregation, and network coding techniques that significantly improve the throughput-delay performance, resource utilization efficiency, and survivability of NG-PON and FiWi networks. Finally, we inquire into the opportunities of sensor-enhanced FiWi networks and propose our novel Über-FiWi network, whose potential is demonstrated by studying the beneficial impact of inter-home scheduling of emerging plug-in electric vehicles on the resource management of a more sustainable future smart grid.