Routing and Spectrum Allocation in Elastic Optical Networks by means of Ant Colony Optimization
The current model of Optical Networks that use Wavelength Division Multiplexing (WDM) has been shown insufficient to meet the traffic demand from services such as IPTV, video on demand, real-time video links, among others which has increased by about 30% a year. One of the most promising solutions to extend the life of current Optical Networks without the need to change the structure already installed is the Elastic Optical Networks (EON). EONs make better use of the spectrum used when performing a better segmentation of bandwidths by allocating them according to traffic needs. With this new technology, there is the Routing and Spectrum Allocation (RSA) problem, which involves choosing a route and allocating the spectrum for each request. In this work, we propose the use of a routing algorithm based on Ant Colony Optimization (ACO) to solve the RSA problem, comparing it with fixed-alternate and adaptive routing algorithms. By performing computational simulations in this work, it was possible to observe that the proposed ACO algorithm allowed the reduction of the bandwidth blocking probability and reached good levels of network restoration capacity after single- node or link failures. It also exhibited setup or restoration times compatible with the other techniques studied in this work while maintained similar levels of network information disseminated through the control channels.