摘要: | 隨著網路的快速發展,頻寬大且速度快的網路需求也就越來越大,但在網路環境中,網路傳輸品質受到多重因素的影響,例如,網路傳輸路徑距離過長便會容易網路傳輸品質的不良,受到外界的影響而造成訊號減弱或干擾過大時,就會造成封包遺失,常常這些遺失又以連續遺失居多,現在在許多的研究上,都盡力於解決這個問題。例如,正向錯誤修正機制(FEC)與交錯式順序機制(Interleaving)。 正向錯誤修正機制(FEC)的原理是將原始的封包之後,加上其原始封包的冗餘封包,利用其冗餘封包的產生,來增大對其原始封包的抗遺失能力,而交錯式順序機制(Interleaving)的原理則為將原始需要傳送的封包,對其做排列順序的改變,然後因為排列順序已被改變,故當發生連續封包遺失時,不至於造成封包因連續遺失,而造成視訊整個片段遺失的情形發生。 於本論文中,我們將利用結合正向錯誤修正機制(FEC)與交錯式順序機制(Interleaving)的方法來計算當遭遇連續性封包遺失時,資料封包的容錯率分析,此研究中,我們也同樣的列出當封包造成連續遺失時,針對其遺失數量,對其做相對應之保護措施,以達到網路傳輸最佳化品 質之需求。 With the rapid development of network, we need more bandwidth and network is fast, but in a network environment, network transmission quality is affected by multiple factors, for example, the network transmission path distance is too long will be likely poor quality of network traffic, by external influence or interference too much will also cause the signal weakened, then packet loss will occur, this lost is often continuous loss., there are many researches for solving this problem. For example, Forward Error Correction (FEC) and Interleaving. Forward error correction (FEC) means it adds a redundant packet after the original packet, to increase the protection for packet loss. Interleaving mean it does a change for the order of packet, and because the order has been changed, so when the continuous packet loss occurs, not cause the clip of video loss. In this paper, we will use the combination of Forward Error Correction (FEC) and Interleaving method to calculate when the continuous packet loss occurs, we can accept how many packet loss. In this research, we also list the continuous packet loss occurs, the quantity for the missing, to do their corresponding measures of protection, in order to achieve optimal network transmission quality. |