今日的網際網路僅對資料提供儘可能的品質服務，若要針對提供個別資料流差別服務，必須針對每個資料流去作資訊維護的工作，如此一來，會增加高速網路中核心路由器的負載。在本篇論文中所提出的差別式網路架構下，我們提出針對頻寬和延遲提出等比例分配的機制，此機制減少維護個別資流資訊的複雜度，且能提供相同的效能。首先，我們針對每個等級的資料，利用Bloom Filter的方式預估其中所包含的活動資料流數目，並根據所預估的資料流數利用權重公平佇列的方式，動態地分配頻寬給每個等級，其次，我們所採用一種變形的RED的佇列管理機制，其能根據資料流數目和佇列長度，動態調整丟棄封包的機率，以達到穩定佇列長度的目的，因此，我們能藉由所分配的頻寬以調整佇列長度，即控制每個等級間的資料延遲，並能保證一定的延遲上限。這篇論文中整理了關於頻寬分配的相關機制，同時經由詳細的模擬，證明我們所提出的機制可以達到相當好的效能，提供各種等級資料流差別式的品質服務保證，並且適用於各種網路狀態。

In order to save network capacity there are efforts to integrate different services such as voice, video, and data. Since the different applications have particular requirements, it is necessary to provide and guarantee different levels of Quality of Service (QoS). The differentiated services concept which classifies the network traffic into different classes has the potential to save capacity and provide different levels of service.

The Assured Forwarding Per Hop Behavior (AF PHB) standardized by the Internet Engineering Task Force (IETF) Differentiated Services working group provides class-based differentiated IP services. In this relative QoS model, services obtained by different classes are proportional. However, services differentiation among classes may cause the unfairness of each flow. Therefore, we propose a dynamic Weighted Fair Queuing (WFQ) scheduling scheme to ensure the proportional fairness of each flow belong to different classes. This scheme dynamically changes the scheduler’s weights to be proportional to the estimation of active flow number of each class. In this way, services allocation can be more efficient and more feasible. By limiting the buffer size adequately, we can also guarantee proportional delay bound in the worst case.

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