正如我们在第一章所学的，端到端时延中最为复杂和有趣的成分就是排队时延。在这个程序中，可以设置分组发送速率和链路传输速率，你将会看到分组到达和为接受服务而排队。当队列变满时，将会发生分组溢出，也就是丢包-As we learned in the first chapter, end to end delay of the most complex and interesting elements is the queuing delay. In this program, you can set

分组交换网络中离散事件仿真(包括单一队列模拟和网络模拟)，计算其丢包率以及延迟。-Build a discrete-event simulator for a packet-switched network and to evaluate its performance, in terms of loss rate and delay, under two operational scenarios.