@article{oai:nagoya.repo.nii.ac.jp:02002843,
 author = {HASEGAWA, Hiroshi and YASUDA, Takuma and MORI, Yojiro and SATO, Ken-ichi},
 issue = {12},
 journal = {IEICE Transactions on Communications},
 month = {Dec},
 note = {We propose an efficient network upgrade and expansion method that can make the most of the next generation channel resources to accommodate further increases in traffic. Semi-flexible grid configuration and two cost metrics are introduced to establish a regularity in frequency assignment and minimize disturbance in the upgrade process; both reduce the fragmentation in frequency assignment and the number of fibers necessary. Various investigations of different configurations elucidate that the number of fibers necessary is reduced about 10-15% for any combination of upgrade scenario, channel frequency bandwidth, and topology adopted.},
 pages = {1514--1523},
 title = {Fragmentation-Minimized Periodic Network-Bandwidth Expansion Employing Aligned Channel Slot Allocation in Flexible Grid Optical Networks},
 volume = {E104B},
 year = {2021}
}