利用頻譜分析之非同步傳輸模式網路鏈路容量配置

Abstract

在寬頻整合服務數位網路的非同步傳輸模式中, 訊務控制是個重要的問 題, 在以往已被廣泛的討論過. 然而在這些研究中, 都是以時域的觀點 來探討系統的效能, 往往忽略了那些才是影響系統效能的重要元素.在此 篇論文中, 我們利用頻譜分析來探討非同步傳輸模式網路中的鏈路容量 配置策略. 頻譜分析可以幫助我們很容易的從輸入訊務的功率頻譜來觀 察系統行為, 進而找出影響系統效能的重要元素. 在此我們將訊務分成 兩大類: 即時性訊務和非即時性訊務, 並且定義一個效能基準以穫得最 佳的系統參數. 研究結果顯示, 輸入訊務的功率頻譜和系統效能之間有 著重要的關係, 並且功率頻譜的低頻帶部份對系統效能有重大的影響. Traffic control is an important issue of asynchronous transfer mode (ATM) for broadband integrated service digital network (B-ISDN) and has been widely studied in past. However, those studies analyzed system performance in view of time domain such that they seldom took notice of what the essential components that impact system performance are. This thesis studies link capacity assignment with different scheduling policies for an ATM network by using spectral analysis. The spectral analysis can help us easily investigate the system behavior of the ATM network from the viewpoint of power spectrum of input process in frequency domain such that to find out essential components that impact the system performance. We classify the traffic into two categories: real-time and non-real-time traffic, and define a performance criterion to search for the optimal system parameters. The results show that the power spectrum of input process has essential relationship with the system performance and the low frequency band of power spectrum has significant impact on system performance.