Simmons J.M. Optical network design and planning

2-d ed. 529 p., 2014 Springer International Publishing SwitzerlandOptical networking has greatly matured since the early 2000s. Optical bypass, where connections remain in the optical domain as they traverse network nodes, is now a well-accepted technology for reducing the amount of electronic equipment in the network. The industry emphasis has shifted from transformative innovations to technological and architectural advancements that address operational and network management challenges. Some of the more important areas of development include network configurability, energy consumption, and fiber capacity. Carriers readily appreciate the advantages afforded by automating the network provisioning process. Remote configurability of the network equipment via software reduces the amount of required manual intervention, thereby allowing more rapid provisioning of services and quicker revenue recognition. To reap the full benefits of a configurable network, the network equipment must be as flexible as possible, within the bounds of cost effectiveness. The network equipment that enabled optical bypass was a major departure from legacy equipment, with significant capital-cost reduction being the main driver of the technology. However, the main motivators guiding network element development today are reduced operational cost and greater network flexibility, where limitations imposed by the equipment are removed. The next frontier in automated connection setup is dynamic optical networking, where connections can be established on the order of a second. Furthermore, the requests for shifts in bandwidth come from the networking layers that sit atop the optical layer (e.g., the Internet Protocol (IP) layer), as opposed to operations personnel. Most carriers have been slow to embrace dynamic optical networking, similar to the initial skepticism regarding optical-bypass technology.