現今大部分的內容調整最適化的方法均致力於為網路應用帶來新的功能或是效能改善，其主要目標還是放在促進每單位的效能提升。根據大部分的內容調適方法類型，基本上大致可分成三種︰1)伺服器端調整、2)代理伺服器端調整、以及3)網路服務調整。雖然大量的內容調整最適化方法不斷地被提出，然而分析比較他們之間效能差異的研究卻寥寥無幾。所以這份研究主要目的是希望藉由模擬實驗的方式，分析比較三種內容調整方法間的效能差異。在本文中，測試了五種不同因子對內容調整方法效能的影響︰1)客戶的內容請求率、2)內容調整子程序的數量、3)完成一個內容調整子程序所需的處理時間，以及4)網路延遲時間。研究結果顯示了一些有價值的資訊，這些資訊可用作內容調整之網路最適化的重要參考指引。

The most traditional approaches to network optimization focuses on bringing new or improved capabilities to target functional areas of network operations. The goal is to boost the unit’s efficiency and effectiveness. Basically, there are three different approaches proposed to help in designing adaptive multimedia systems for heterogeneous devices: server-side adaptation, proxy-based adaptation, and service-based adaptation. Though there are a variety of approaches being proposed, evaluating content adaptation approaches is still lacking. This study shows a simulation effort to evaluate and compare the differences among those three kinds of content adaptation approaches. A 2 by 4 factorial design simulation is implemented to test the effects of five different influential factors within the network: 1) client’s request rate, 2) number of adaptation sub-process, 3) process time of an adaptation sub-process, and 4) network latency time. The result shows some valuable information and could be used as a key reference for the optimization of content adaptation network.

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