**8. Conclusion**

Exploring methods for the processing of signals in the optical domain, the chapter includes the solutions for the efficient transport of heterogeneous traffic by enhancing the flexibility of the optical layer in allocating network resources as well as for the implementation of an adaptable infrastructure that provides on-demand functionality according to traffic requirements. Further provides a comprehensive review of the state-of-the art of optical signal processing technologies and devices. It presents breakthrough solutions for enabling a pervasive use of optical signal processing to overcome the capacity crunch in optical fiber applications. The chapter content ranges from the road map toward elastic optical networks, optical switching paradigms, need for elastic optical node and application that support gridless node in optical communication having the ability of repositioning signals in a fragmented spectrum by all-optical signal processing functionalities such as MC, spectrum defragmentation, FC, WC and grooming of high speed signals in order to maintain a proficient resource utilization.

*Optical Fiber Applications*
