现代交换原理讲义CH1_交换概论ch2 通信信源模型-new070327_new-2CH2_交换网络ch3_Erlang拒绝和等待系统CH3_数字程控电话交换与电话通信网ch4_通信网络性能分析CH4_信令系统CH5_分组交换与分组交换网ch5_网络拓扑结构分析CH6_ISDN交换与综合业务数字网ch7_网络可靠性分析-Principles of modern exchange notes Introduction CH1_ exchange communication channel ch2 source model-new070327_new-2CH2_ exchange network ch3_Erlang refused to wait for CH3_ digital program-controlled telephone systems and telephone communications network to exchange ch4_ Communication Networks Performance Analysis of Signaling System CH4_ division CH5_ network switching and packet switching network topology ch5_ analysis CH6_ISDN exchange and integrated services digital network analysis of network reliability ch7_