Elastic optical networks are extremely effective networks for high speed optical communication owing to excessive data rate requirements in future years. Applying the space division multiplexing (SDM) technology with multi-core fibers (MCFs) provides possibility to increase the network capacity and data transmission rate as a consequence. One of the main issues in these types of networks is bandwidth fragmentation due to dynamic spectrum allocation and releasing. Management of this problem would lead to optimal use of network bandwidth. As a result, more connection demands can be accommodated. In this paper, two novel algorithms of multi-path routing are presented to improve fragmentation, where both algorithms are fragmentation-aware. The first algorithm, named Fragmentation-aware Best Splits (FABS), exploits fragmentation criteria as well as a new split technique called Best Split. In addition to these features, the second algorithm called Crosstalk-aware Best Split (CABS) considers inter-core crosstalk (XT) which is a significant issue in SDM. By employing these two algorithms and considering distance-adaptive modulation, our performance evaluation results illustrate a remarkable improvement in reducing blocking rate and enhancement of spectrum utilization.

由于未来几年对数据速率的要求过高，弹性光网络是用于高速光通信的极其有效的网络。将空分复用（SDM）技术与多芯光纤（MCF）结合使用可以提高网络容量和数据传输速率。这些类型的网络中的主要问题之一是由于动态频谱分配和释放导致的带宽碎片。管理此问题将导致网络带宽的最佳利用。结果，可以适应更多的连接需求。在本文中，提出了两种新颖的多路径路由算法来改善分段，这两种算法都支持分段。第一种算法称为“感知碎片的最佳拆分”（FABS），利用碎片化标准以及称为“最佳拆分”的新拆分技术。除了这些功能之外，第二种称为“串扰感知最佳拆分”（CABS）的算法考虑了内核间串扰（XT），这是SDM中的重要问题。通过采用这两种算法并考虑距离自适应调制，我们的性能评估结果说明了在降低阻塞率和提高频谱利用率方面的显着改进。