In this paper, we study the quality of transmission (QoT) aware routing, modulation level, and resource assignment problem for transparent flexible optical networks over few-mode multi-core fibers. We consider two three-dimensional resource assignment (3DRA) algorithms, called liberal and conservative, that are compatible with fractional joint switching. The three resource dimensions are core, mode, and spectrum. Furthermore, we analyze two modulation-level selection (MLS) algorithms (one on-line and one off-line) and three path selection algorithms (favoring shortest path, best balanced load, or highest QoT). The results show that the liberal 3DRA algorithm has a similar blocking probability (BP) compared to conservative 3DRA. However, performance metrics such as computation time, optical signal-to-noise ratio (OSNR), and number of required lasers are all improved with conservative 3DRA. Moreover, the BP decreases and the average OSNR increases by applying the on-line MLS algorithm compared to the off-line algorithm. Finally, we use an on-line liberal algorithm with a path selection policy that favors load balancing to generate a solution with the lowest BP.

中文翻译：

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FM-MCF上频谱空间灵活的光网络的QoT感知性能评估

在本文中，我们研究了在少模多芯光纤上的透明柔性光网络的传输质量（QoT）感知路由，调制级别和​​资源分配问题。我们考虑了两个称为自由和保守的三维资源分配（3DRA）算法，它们与分数联合切换兼容。资源的三个维度分别是核心，模式和频谱。此外，我们分析了两种调制级选择（MLS）算法（一种在线和一种离线）和三种路径选择算法（有利于最短路径，最佳平衡负载或最高QoT）。结果表明，与保守3DRA相比，自由3DRA算法具有相似的阻塞概率（BP）。但是，性能指标包括计算时间，光信噪比（OSNR），保守的3DRA可以改善所需的激光器数量。此外，与离线算法相比，通过应用在线MLS算法，BP减小，平均OSNR增大。最后，我们使用具有路径选择策略的在线自由算法，该策略支持负载均衡以生成具有最低BP的解决方案。