有限波长转换能力光突发交换网络动态波长分配机制

Dynamic Wavelength Assignment Scheme for OBS Networks with Limited Wavelength Conversion Capabilities

为了解决下一代可商用化的有限波长转换能力光突发交换(OBS-LWCC)网中突发包资源竞争问题,根据波长转换器所在的位置分布,将整个网络解构为多个波长连续性子段.基于分解后的网络模型,对各种波长分配算法的突发阻塞性能进行分析和综合比较,采用传统优先级计算与子段模型结构相结合的方法,提出一种新的分布式动态波长分配策略PWA-leg.仿真实验表明,在OBS-LWCC网络结构中关键的波长可转换节点处,该算法实现了突发业务最佳承载波长(信道)的智能选择,与传统波长分配算法相比,具有更低的全网突发包阻塞率,能够更好地适应动态突发包业务和网络拓扑的变化.

The problem of burst contention in the future commercial optical burst switching （OBS） networks with limited wavelength conversion capability （LWCC） was investigated. According to the position of wavelength converters, the network architecture was decomposed into multiple wavelength-continuous segments, named as a ＂leg＂. Based on the decomposed network model, various conventional wavelength assignment algorithms were analyzed and compared. Furthermore, a novel distributed dynamic wavelength assignment policy called PWA-leg was presented, combining the conventional priority calculation and the new leg structures. The simulation experiments indicate that, in the OBS-LWCC networks, the proposed algorithm which can intelligently assign the optimal wavelengths to diverse burst traffics at the wavelength convertible switches is proved to always obtain the lowest blocking probability, and consequently, is more compatible to the dynamic burst traffics and the topology changes, compared with the previous algorithms.