Novel fragmentation-aware algorithms for multipath routing and spectrum assignment in elastic optical networks-space division multiplexing (EON-SDM)

摘要

An innovative technology to expand transmission capacity of optical backbone networks and to add flexibility to conventional WDM networks is Elastic Optical Networks with Space Division Multiplexing (EON-SDM). In EON-SDM, connection requests can be established in a much efficient manner than WDM networks and even EON network without SDM capability. The notion of increasing fiber capacity with Space Division Multiplexing (SDM) is almost as old as fiber communications itself. One of the important problems in EON-SDM is fragmentation created by dynamically establishing and releasing lightpaths over time, thus increasing connection blocking probability. In this article, three novel algorithms are introduced to resolve fragmentation problem and improve blocking probability in EON-SDM; called Fragmentation Measure Metric Aware with Routing and Spectrum and Core Assignment (FMMA-RSCA), Most Fragmented Path per Core (MFPC), and Spectrum Block Multipathing per Core (SBMC). These algorithms can reduce blocking probability by controlling fragmentation in cores since they try different ways in order to assign spectrum for a given connection request. By providing this opportunity in spectrum allocation and assignment, connection blocking probability is improved as proved based on our performance evaluation results.