ABSTRACT
Spectrum fragmentation management approaches are used to handle spectrum fragmentation and increase the admissible traffic levels in the network. This chapter presents spectrum fragmentation management approaches considering non-defragmentation. In the non-defragmentation approach, necessary precautions are taken to avoid fragmentation before the establishment of a lightpath. Dedicated partitioning approaches are the more strict version of the pseudo partitioning approach. In dedicated partitioning approaches, the entire spectrum is divided into a number of partitions based on certain criteria, and each partition is dedicated to a different lightpath group. The chapter explains how the lightpath groups are created based on disjoint and non-disjoint routes of lightpath requests. To separate the disjoint and non-disjoint lightpaths, lightpath requests are categorized into two groups, namely disjoint lightpath group and non-disjoint lightpath group. Fadini et al. introduced a dedicated partition scheme that reduces call dropping by separating the disjoint and non-disjoint lightpaths into different partitions.
