Fragmentation Suppressed RSA Algorithm for Elastic Optical Network: A Quantitative approach

Fragmentation is a complicated issue during online resource allocation in Elastic optical network (EON). It becomes more complicated if the connection is assumed to be dynamic in nature. In this paper for the dynamic (increase) connection, the probability density function of unused and used optical band is calculated. The role of smaller unused frequency slots on the spectral utilization is extensively analyzed through simulation. We propose a quantitative metric to quantify the fragmentation in a link. On the basis of metric, we propose a routing and spectral algorithm called Fragmentation suppressed RSA (FS-RSA). Our proposed FS-RSA helps in accommodating more number of connection by decreasing the fragmentation as compared to the conventional First fit and Random fit. The proposed scheme takes lesser computational time as compared to MinEnt RSA.