在ATM網路中的OAM測量與警報相關性之研究

Abstract

本論文係針對未來之寬頻整合服務數位網路(B-ISDN)所採用的高速交換技 術，即非同步傳輸模式(Asynchronous Transfer Mode, ATM)，進行網路 管理方面的研究。本研究包含在 ATM 中 OAM 測量的方法與警報相關性( Alarm Correlation)之研究。在本篇論文中，我們概略敘述 OAM 的錯誤 管理與效益管理機制，並提出路徑交集(path intersection)的假想方法( heuristics)，將網路上 OAM 測量所收集到的警示訊息進行分析與歸納， 判斷網路上可能發生擁塞的位置與影響的區域。為了驗證我們方法的可行 性與優劣性，我們以模擬來評估我們方法的效能並分析其結果。此外，我 們利用模擬的結果對網路的擁塞模式(congestion pattern)加以研究。最 後，我們利用此假想的方法提出三種選取虛擬路徑(Virtual Path, VP)路 徑調整(reroute)的方法以解決網路擁塞並比較其優劣。 The purpose of this thesis is to research on network manage- ment of Asynchronous Transfer Mode (ATM) which is adopted as the core technology of B-ISDN. Our research includes OAM measurement and alarm correlation methods in ATM networks. In this thesis, we introduce the OAM fault management and performance management mechanisms. We present the path intersection heuristic as the alarm correlation method to analyze the alarms collected by OAM measurements, and to find the congestion areas in ATM networks. We use simulation to evaluate the proposed heuristics. Besides, we analyze the congestion pattern in ATM networks by examing the simulation results. Finally, based on the proposed heuristics, we present three methods to choose the VPCs for rerouting in order to eliminate the congestion and we make a comparison among these three methods.