群播傳輸網路系統安全之研究

Abstract

群播傳輸(Multicast)藉由其傳輸機制，在一對多(One-to-Many)或是多對多(Many-to-Many)的通訊中，得以極有效率地傳輸聲音、影像等諸項資料，然而群播傳輸亦因採用使用者資料報協定(UDP,User Datagram Protocol)傳送資料─資料封包遺失時，傳送端不會重新傳送。於是當遭受攻擊並導致封包遺失時，將影響群播傳輸網路原有之運作效能。\n為分析攻擊對運作效能的影響，本文採用NS-2(Network Simulator-2)作為模擬工具，並訂定評估運作效能的參數，再分別模擬傳送端及接收端進行攻擊的模式，藉由模擬與統計所得的數據，進一步了解，當群播傳輸網路遭受攻擊時，將會有何種程度的影響。

Multicast distributes voice and video efficiently under one-to-many or many-to-many communication by its transport mechanisms. However, Multicast transmits data by using User Datagram Protocol which the packets lost, senders will not be re-transmit. When it is under attack and lead to packets lost, the original performance of Multicast will be affected.\nIn order to analyze the performance affected by attack, we use NS-2 for simulation tool. Then we define the matrix which use for evaluates the performance. So we can understand the level of influences further which take place when Multicast is under attack.