任意傳收器調諧延遲光纖網路中無碰撞排程演算法

Collisionless Scheduling Algorithms with Arbitrary Transceiver Tuning Latencies in DWDM networks

陳宣治(Hsuan-Chin Chen)

指導教授 ： 黃依賢

元智大學/資訊學院/資訊工程學系/碩士(2001年)

摘要

由於網路的蓬勃發展，加上多媒体(multimedia)技術的應用，使得現有的頻寬己逐漸不敷使用，透過光纖網路可以提供較多的頻寬，故得在固定的頻寬中，使用良好的排程演算法，來增進頻道的重覆使用率，和網路的整體效率。就目前波長分割多工(WDM) 的排程演算法而言，大略可分成三種主要方式:Random access-based protocol 、Pre-allocation-based protocol 以及Reservation-based protocol，本文裡，首先概述個別的工作原理。接著描述所摘錄下來，以Reservation-based protocol為主的六個排程演算法工作原理。而本文所提出的無碰撞(collisionless)排程演算法是以廣播式被動星形隅合器(Passive Star Coupler (PSC))連結的光纖網路架構為主，不但能夠解決之前六個演算法在單一對資料頻道的傳收器中，單次跳躍傳輸可能發生封包碰撞與傳收器困擾的問題，同時我們也考慮收發器的轉換延遲(tuning latency)對整個系統的影響，甚至可適用於Multi-transmission behavior之機制。我們利用模擬程式來評估演算法對於三種不同傳收端(transceiver)架構；評估演算法於multi-transceiver model的效能，包括以節點數、封包數與頻道數為操縱變因的頻道使用率(channel utilization)、平均封包延遲(average packet delay)與輸出率(throughput)。以提供此演算法對不同網路架構彈性運用當參考。

關鍵字

Multi-transceiver model : TT-TR ； FT-TR ； TT-FR ； Multi-transmission behavior : point-to-point ； multicast ； broadcast

並列摘要

Due to the booming development of network and technical applications of multimedia, the provided bandwidth of the current technology are gradually not enough. The fiber-optic network is a perspective emerging broadband high-speed network could provide much more bandwidth. Furthermore, one important issue is that how we use well-scheduling algorithm in fixed bandwidth to increase the repeat usage of channel and the whole efficiency of network. The scheduling algorithms of current passive star coupler (PSC) WDM networks can be mainly divided into three categories: Random access-based protocol, Pre-allocation-based protocol and Reservation-based protocol. In this thesis, we describe and compare the work principle of six scheduling algorithms that are based on reservation-based protocol. Unfortunately, two important issues are not discussed in the previous papers that are transceiver conflict and tuning latency. In this thesis, the collisionless scheduling algorithm with arbitrary transceiver tuning latencies is proposed based on the fiber-optic network topology using broadcast PSC connection. It can’t only solve the packet collision and transceiver conflict problem during point-to-point transmission, but also we consider the impact of tuning latency on system performance. The proposed scheduling algorithm can also be applied to multicast and broadcast mechanisms. Three different transceiver frameworks (TT-TR, FT-TR, and TT-FR) are investigated and compared in detail by computer simulations. The performance of multi-transceiver models are evaluated in terms of the average packet delay, throughput and channel utilization varied with different number of nodes, packets and channels.

並列關鍵字

Multi-transceiver model : TT-TR ； FT-TR ； TT-FR ； Multi-transmission behavior : point-to-point ； multicast ； broadcast

參考文獻

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