多單位交換在階層式光交換器光纖網路下之效能分析

Abstract

階層式光交換器的出現是為了解決傳統分波多工光纖網路上光交換器在製造與維護上的擴充性問題。雖然目前已有各種的交換器架構以及其所對應的啟發式演算法被提出，這些架構對於未來網路鋪設時的成本效益卻尚未被廣泛的討論過。在這篇論文裡，我們針對兩種利用多單位交換的網路，用一個以啟發式演算法為基礎的方法來比較這兩種網路的效能，以期望能選出較符合成本效益的網路。我們所用的啟發式演算法具有簡單性的特性，它們主要是先把給定的網路資源轉換成一個輔助的圖，然後在這個圖上為每個連線要求尋找路徑，其中，每個連線要求找到路徑以後需要對這個圖上的邊做一些更新來反應所剩餘的網路資源。論文最後我們會進行模擬測試來驗證所提出的演算法，以及比較兩種網路的效能。比較的結果對於網路服務者在設計網路時提供了相當大的幫助。

Hierarchical optical cross-connects (OXCs) has emerged as a means to solve the scalability problem in manufacturing and maintenance of the traditional OXCs which are used in the wavelength division multiplexed (WDM) networks. Although various architectures and corresponding heuristics have been proposed, not much has been discussed on the cost-effectiveness between those architectures for the future deployment. In this paper, we target on two types of networks that utilize multigranularity switching and use a heuristic-based approach to compare the performance of the two networks so that the better one can be chosen. The heuristics possess the simplicity by first transform the given network resources into an auxiliary graph and then base on which shortest path algorithm is applied to route the requests, with some manipulation on the edges to reflect the remaining network resources. Simulation is conducted to validate the heuristics we use and the outcome of the comparison is helpful for the network service providers when designing a cost-effective network.