In this paper, a reactive defragmentation rerouting and spectrum assignment (RDRSA) strategy when existing connection requests terminated and network resources released is presented. In RDRSA with spectrum conversion (SC), the existing connections are re-established to new route or reassigned to new frequency slots. Defragmentation has three advantages over the conventional RSA: (1) at the time of connection setup, shorter routes may be unavailable, but after the termination of the existing requests; possibility of re-assignment of shorter route becomes high, (2) fragmentation of network also reduces which results load balancing over the entire network, (3) network resource utilization increases due to more connection acceptance. The performance of RDRSA-SC is compared with the conventional RSA with spectrum conversion (SC), and non spectrum conversion (NSC). The simulation results on NSFNET and ARPANET network topologies show that the proposed RDRSA-SC has lower fragmentation and bandwidth blocking probability, and more utilization of network capacity than the existing RSA-SC and RSA-NSC.

在本文中，提出了一种当现有连接请求终止并释放网络资源时的反应式碎片整理重路由和频谱分配（RDRSA）策略。在具有频谱转换 (SC) 的 RDRSA 中，将现有连接重新建立到新路由或重新分配到新频率槽。碎片整理相对于传统的 RSA 有三个优点：（1）在连接建立时，较短的路由可能不可用，但在现有请求终止后；更短的路由重新分配的可能性变高，（2）网络的碎片化也减少了，从而导致整个网络的负载平衡，（3）由于更多的连接接受，网络资源利用率增加。将 RDRSA-SC 的性能与具有频谱转换 (SC) 的常规 RSA 进行比较，和非频谱转换（NSC）。NSFNET 和 ARPANET 网络拓扑的仿真结果表明，与现有的 RSA-SC 和 RSA-NSC 相比，所提出的 RDRSA-SC 具有更低的分片和带宽阻塞概率，以及更多的网络容量利用率。