WDM網路下具有少量光分割及波長轉換功能節點配置問題之研究

Abstract

分波多工(Wavelength Division Multiplexing，WDM)網路使用波長路由的方式傳送資料之技術已確定成為下一代網路的主要架構。為能利用少量的波長(wavelength)及波長通道(wavelength channel)來達到群播(multicast)傳送的目的，因此，在光學交換器上提供具有光分割(lightsplitting)及波長轉換(wavelength converter)功能，此交換器亦稱為VS(virtual source)節點。VS節點成本較高，故一般僅有部份節點具有VS功能，透過配置具有VS功能節點及決定群播的傳送路徑，建構出群播樹(multicast tree)，以使得群播所使用的波長及波長通道數最少是一個值得研究的問題。本論文主要研究在WDM網路環境下，如何配置VS節點，給定一些群播的需求，在需要配置k個VS節點時，使得群播之效能為最佳的問題。本論文中提出基因演算法來解決此問題，並透過實驗數據來了解成果。

Wavelength routing together with wavelength division multiplexing (WDM) technology have been considered as a strong candidate for future high performance networks. In order to make use of a small amount of wavelengths and wavelength channels to achieve the purpose of multicast effectively. It is offered the node which has splitting and wavelength converter switch, this node is also called VS (virtual source) node. The topology network via placement the node with VS switch, and determine suitable multicast routing to construct the multicast tree. That makes the multicast tree use the number of wavelengths and wavelength channels can be minimized. In this paper a genetic algorithm (GA) is proposed to solve this problem. Experiments are also given to show the efficiency of GA.