The Photonics Advancements in the Emerging Zettabyte Network Architecture

This tutorial reviews the significant advancements in photonics system, technology, standards, and associated evolution of network architectures starting from long-haul, and more recently multi-service metro networks, and extending into the emerging IP-over-WDM core and packetoptical metro networks. We first analyze the functional characteristics and challenges of these networks, and review the current and emerging applications that motivated these networks to scale levering WDM transport. We particularly discuss how the new, high-bandwidth, predominantly video related, applications (including IPTV, video-on-demand, peer-to-peer, and video-conferencing), often with diverse quality-of-service requirements, are increasingly motivating a fundamental shift in services from circuits to packets, giving rise to the most significant evolution of transport networks in recent history. The tutorial then focuses on the current and future converged WDM transport. We analyze how WDM improves significantly the network capital and operational cost, and evaluate the interplay among the network architectures, system design, and the enabling photonics technology innovations. Unlike traditional WDM systems where the main design objective has been to maximize the capacity and reach of networks with well-defined (typically simple point-to-point) topologies, converged WDM networks call for "open" architectures that allow for cost-sensitive service flexibility. We discuss in detail the innovations in WDM system design, and the current and emerging photonic technologies; including most notably reconfigurable wavelength opticaladddrop (OADM) and switching, and advancements in transmission of 40 and 100 Gb/s channels leveraging new modulation formats, and electronic signal processing. These innovations collectively have enabled fiber communication systems that cost-effectively scale to Tb/s and thousands of km, and the emerging Exabyte public IP network infrastructure. Future network evolutio- - n, emerging standards, and related research topics are also being considered.