The introduction of elastic optical networks (EONs) leads to new challenges, such as the problem of routing, modulation level, and spectrum assignment. In the literature, the best among the shortest routes (BSR) algorithm was proposed as fixed and fixed-alternate routing for EONs, but without considering physical impairments. Therefore, call requests were handled not taking into account the different bandwidth requirements as well as the impact on the optical signal quality of transmission when different modulation levels are considered. This is the first study to undertake heuristics based on BSR algorithm considering a fixed-alternate routing approach jointly with physical layer constraints in EONs. In order to assess the effectiveness of the proposed BSR heuristics in this paper, a genetic and a particle swarm optimization algorithms were also proposed. The results obtained by numerical simulations in different network physical topologies available in the literature show the effectiveness of our proposals in reducing the blocking probability of call requests in comparison with the traditional Yen algorithm.

中文翻译：

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应用于弹性光网络的损伤感知固定交替 BSR 路由启发式算法

弹性光网络 (EON) 的引入带来了新的挑战，例如路由、调制级别和​​频谱分配问题。在文献中，最短路由中的最佳 (BSR) 算法被提议为 EON 的固定和固定交替路由，但没有考虑物理损伤。因此，在处理呼叫请求时没有考虑不同的带宽要求以及在考虑不同调制级别时对传输光信号质量的影响。这是第一个基于 BSR 算法进行启发式的研究，考虑固定交替路由方法和 EON 中的物理层约束。为了评估本文提出的 BSR 启发式算法的有效性，还提出了遗传和粒子群优化算法。通过文献中可用的不同网络物理拓扑的数值模拟获得的结果表明，与传统的 Yen 算法相比，我们的建议在降低呼叫请求阻塞概率方面的有效性。