多光纖多波長格狀網路之研究

Abstract

本篇論文提出並探討一個異於一般波長多工方式、融合空間及波長區隔、 由多光纖及多波長架構而成的格狀網路。在此網路中，總數為 MN 之節點 被安排成一 MxN 的矩陣。我們使用一含 N 條光纖之光纜來連結矩陣中每 一列的所有節點。同樣地，在每一行中的所有節點則用一含 M 條光纖之 光纜加以連結。在每一列中，我們使用了 N 個波長。經由特殊的安排， 使在同一列中的所有節點能達到彼此完全連結。同樣的情形亦應用在每一 行中，唯其使用波長數由 N 改 M 。此種多光纖、多波長之格狀架構擁有 許多特點：首先，其邏輯通道與實體光纖有相同的幾何結構，且符合實際 多心光纜之佈放實況，因此可極為容易地建構。再者，其將欲建立 N 個 節點間完全連結所需之波長數，從以全波長區隔方式下所需之 N(N-1) 個 減低至僅需 N 個波長，並且，在每一節點均僅需 1 個發射波長，大大減 低此網路之複雜度。本網路並擁有極高的通訊量，且封包之平均躍遷級數 小於 2。任一節點均可隨時送出封包而毋需競爭等候發送權，封包之傳送 延遲可因此而降低。經由多重路由之特色，此格狀網路亦擁有良好的失效 保護能力。此一多重路由特色不僅提昇網路的存活性，並且大大提昇封包 的到達率。 This thesis investigates a novel WDM network - the Multiwave- length Multifiber Regular Grid Network (MMRGN) which combines space and wavelength divisions to construct a multihop multi- wavelength network. In the network, a total number of MxN nodes are arranged as an MxN matrix. A cable consisting of N fibers is employed to connect N nodes in each row of the matrix and M fibers in each column. N wavelengths are used in each row in a way that full mesh connection among nodes is built. The same situation occurs in each column except that N is replaced by M. The proposed approach has the same physical and logical topology and can be implemented easily. It reduces the wavelength requirement among N nodes from N(N-1) to N comparing to a full wavelength division approach. Moreover, each node just has one transmitting wavelength only. The network has high throughput and has a mean hop number less than two. Packets can always be delivered immediately without competing the right for transmission and thus reduces the transmission latency. Protection against link failures is achieved by diverse routing paths, which improves network survivability and enhances packet reachability.