A Novel First Random Fit (FRF): Dispersion Aware Approach using Heuristic and ILP in Elastic Optical Network (EON)

Abstract

The capacity of Elastic Optical Network (EON) to dynamically employ network resources is drawing a lot of interest these days. Access to spectrum resources is challenging for new requests especially when the spectrum is divided into numerous tiny segments. The distribution of spectrum, intelligent and effective routing are two other major EON challenges. In order to allocate contiguous aligned spectrum slots to multiple requests, this includes searching for a certain route. EON seeks to maximize connectivity while utilizing the least amount of spectrum resources possible in this manner. Given that dispersion is a significant physical problem in optical networks, this research investigated a method of spectrum distribution using first random fit (FRF) method. This plan takes dispersion into account while performing the spectrum allocation strategy. This system tends to allocate more connection requests and use spectrum more effectively when using a FRF strategy. This technique employs and assigns the spectrum slot to the longest photonic route starting from the lowest indexed slot using the First Fit algorithm while using a less reliable modulation technique like BPSK. Using a more stable modulation technology (QPSK) in combination with a random fit assignment method, it is possible to utilize the next higher indexed spectrum spot which has a bigger impact on dispersion to the shortest photonic path. Advantage of using a heuristic approach for large scale network can be quantitatively measured in terms of computational efficiency and scalability. Till now, as per our knowledge FRF technique with ILP approach considering dispersion as one of the parameter has not been covered yet. The finding demonstrate that the suggested method outshines the previous distance adaptive and non distance adaptive spectrum allocation schemes in terms of distinct parameters as fragmentation (0.9966), CASR (0.0033), blocking probability (BBP) of 0.048, blocking probability (B.P) and optimality gap of 4.71 % and other parameters.