Abstract Elastic optical networks (EONs) have realized high-speed data transmission with attractively efficiency and flexibility in resource utilization. In order to guarantee the reliability and increase the efficiency of the multicast transmission in EONs, we propose a multiple leaf-ringing based protection algorithm with spectrum defragmentation (MLRP-SD) in this article. The proposed algorithm firstly sorts the destination nodes of a multicast service into multiple groups. Then, it constructs one leaf ring for all the destination nodes in one group and two dedicated trunk paths (including one protection trunk path) from the source to each constructed ring. Since a leaf ring can provide protection for the destination nodes in its corresponding group, the reliability of multicast traffic can be improved. And the use of leaf rings can reduce the spectrum consumed in service protection compared to the traditional dedicated path protection (DPP) algorithms. In order to further improve the efficiency, the proposed MLRP-SD algorithm triggers spectrum defragmentation to re-optimize resource utilization in the network when sufficient available spectrum resources cannot be found along the sought protection trunk paths. The simulation results show that the proposed MLRP-SD algorithm can guarantee the reliability of multicast traffic with low service blocking probability.

中文翻译：

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基于多叶环的弹性光网络组播流量频谱碎片保护算法

摘要 弹性光网络（EONs）以极具吸引力的效率和资源利用灵活性实现了高速数据传输。为了保证EON中组播传输的可靠性和提高效率，我们在本文中提出了一种基于多叶环的频谱碎片整理保护算法（MLRP-SD）。所提出的算法首先将多播服务的目的节点分为多个组。然后，为一组中的所有目的节点构建一个叶环和从源到每个构建的环的两条专用中继路径（包括一条保护中继路径）。由于叶环可以为其对应组内的目的节点提供保护，因此可以提高组播流量的可靠性。并且与传统的专用路径保护（DPP）算法相比，叶环的使用可以减少服务保护中消耗的频谱。为了进一步提高效率，当沿寻求保护的中继路径无法找到足够的可用频谱资源时，所提出的MLRP-SD算法会触发频谱碎片整理以重新优化网络中的资源利用。仿真结果表明，所提出的MLRP-SD算法能够以较低的服务阻塞概率保证组播流量的可靠性。当沿着寻求保护的中继路径无法找到足够的可用频谱资源时，所提出的 MLRP-SD 算法会触发频谱碎片整理以重新优化网络中的资源利用率。仿真结果表明，所提出的MLRP-SD算法能够以较低的服务阻塞概率保证组播流量的可靠性。当沿着寻求保护的中继路径无法找到足够的可用频谱资源时，所提出的 MLRP-SD 算法会触发频谱碎片整理以重新优化网络中的资源利用率。仿真结果表明，所提出的MLRP-SD算法能够以较低的服务阻塞概率保证组播流量的可靠性。