波带碎片最小化的波带分配算法及性能仿真研究

基于多粒度光交叉连接器（MG-OXC）的波带交换技术可以有效地降低网络对光交换端口数的需求，为此目前提出了许多波带分配算法。但是现有的波带分配算法只考虑如何有效组合波带，而没有考虑波带中的波长利用率问题，已建的未满波带中的空闲波长（即波带碎片）可能不会再被使用到，波长利用率不高。提出了碎片最小化波带分配算法，即WA-MF算法，其主要思想是将新到的业务请求有效地调度到已经建立好的但未完全填满的波带通道中。仿真结果表明：该算法能有效地减少有碎片的波带在网络中的比例，进一步减少网络所需端口数目，有效地改善网络的阻塞性能，并能提高波带中的波长利用率。

Waveband assignment algorithm with minimal waveband fragment and its performance simulation

In optical network, waveband switching (WBS) in conjunction with multi-granular optical cross-connects (MG-OXC) can effectively reduce the requirement of port counts. And so currently, there are various waveband assignment algorithms to be proposed. However, these algorithms only considered how to group several wavelength together as a band, the wavelength utilization in the waveband is not involved, i.e., one single free wavelength in an active waveband which has not been completely filled (such wavelength is called waveband fragment) will never be used, so the wavelength utilization is lower. Therefore, this paper proposes a heuristics assignment algorithm called waveband assignment with minimal fragment (WA-MF), which tries to merge the new coming traffic requests into the waveband that has not been completely filled. The simulation results show that it can effectively reduce the proportion of waveband which contains fragment and the port counts, and improve the block probability and wavelength utilization in waveband at the same time.