关键词: 弹性光网络, 负载均衡, 频谱资源利用率, 阻塞率

Abstract: Under the constraints of spectrum consistency and spectrum continuity, after a period of operation of elastic optical network, a large number of fragments of network spectrum will appear. To address the problem of fragmentation and unbalanced allocation of service among nodes, a routing and spectrum allocation algorithm based on node importance is proposed. Aiming at routing problem, this algorithm considers the type and size of service, finds the key nodes in the network, and makes service allocation balanced. In terms of spectrum allocation, the algorithm can reduce the spectrum fragmentation as much as possible by taking into account the distribution of spectrum resources on the network link and combining the number of frequency slots required for each service. In two network topologies of different sizes, NSFNET and USNET, the proposed algorithm is simulated. The simulation results show that the proposed NIRSA algorithm can not only effectively reduce the traffic blocking rate, but also improve the spectrum utilization rate of the network and realize the improvement of network performance.

Key words: elastic optical network, load balancing, spectrum resource utilization rate, blocking rate