A New Ursane-Type Triterpene from the Roots of Salvia miltiorrhiza Bunge

Abstract

Network coding (NC) has been recently emerging as an excellent technique for leveraging network efciency. In optical networks, NC and protection appear to be a good match and indeed, NC could be efectively exploited for greater protection efciency thanks to the opportunity of combining signals rather than duplication in the traditional approach. Motivated by this observation, we investigate the application of a simple and practical NC technique based on XOR operation to improve the network throughput in survivable optical networks. To this end, we propose the NC-based protection whose speed recovery is on a par with the conventional 1 + 1 dedicated protection while the capacity usage could be more efcient, paving the way for improving throughput in constrained capacity conditions. A novel mixed integer linear programming model is developed for survivable optical networks design employing the proposed NC-based protection. The model attempts to optimally determine the demands to serve, the routing for served demands and NC assignment among demands aiming at maximizing the network throughput in the constraint of bandwidth limitation. Extensive numerical evaluations on realistic topologies are provided to highlight the advantages of our NC-based protection proposal compared with the conventional dedicated protection in improving the network throughput. Encouraging results are observed when the new protection proposal based on NC could accommodate up to 30% more trafc than the conventional case.