A SLOT-PRIORITY SPECTRUM ASSIGNMENT ALGORITHM FOR ELASTIC OPTICAL NETWORKS
Keywords:Bandwidth-Variable Lightpath, Gridless Networks, First-Fit Assignment, Routing and Spectrum Assignment
To overcome the inefficiency of the rigid spectrum allocation in traditional wavelength division multiplexing (WDM) networks, a flexible grid networking paradigm for spectrum allocation has been recently proposed. On these Flexible-Grid Optical Networks, the spectrum is not rigid, but flexible so that spectrum resources can be adaptively provided to client traffic demand. Spectrum allocation is performed by a process known in the literature as the Routing and Spectrum Assignment (RSA). The performance improvement imparted by RSA algorithms on currently proposed Flexible-Grid Optical Networks is a subject of current extensive investigation. In this paper, we propose a spectrum assignment algorithm based on First-Fit spectrum ordering, where slots are prioritized regarding to the number of forms how future variable-bandwidth path requests can be assigned. Case studies were carried out in order to analyze the benefits of the proposal. In the scenarios analyzed the proposed algorithm outperformed traditional First-Fit assignment.
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