ABSTRACT
The performance of the elastic optical network (EON) depends not only on its physical resources, like—transponders, physical links, usable spectral width, optical switches, etc., but also how the network is controlled. The objective of an routing and spectrum allocation (RSA) algorithm is to achieve the best performance within the limits set by the physical constraints. In a dynamic environment, the fragmentation problem cannot be completely eliminated. Therefore, reactive fragmentation-aware RSA algorithms attempt to restore the network’s ability to accommodate high-rate and long-path connections. The traditional wavelength division multiplexing-based optical network assigns spectrum resources to optical paths without considering the appropriate modulation technique, which leads to an inefficient utilization of the spectrum. The EON architecture offers the ability to choose the modulation format and channel bandwidth to suit the transmission distance and quality of transmission desired. The chapter discusses the networking cost reduction made possible by the use of sliceable bandwidth-variable transponders in the EON.
