这里我们把每个客户机通过双绞线、交换机、光收发器、光纤、光收发器到服务器的链路称为“信道”。每条信道的质量往往是由双绞线、光纤的长度、和客户机、交换机、光收发器、服务器的质量决定的。 一般来说,用带宽来描述模拟信道的容量。用数据速率来描述数字信道的容量。(但是,在许多资料上也借用带宽这个词来描述信道的容量。比如说某信道的带宽56kb/s,也就意味 Here we call each client through the twisted pair, switches, optical transceivers, optical fiber, optical transceiver to the server link called “channel.” The quality of each channel is often determined by the twisted pair, the length of the fiber, and the quality of the client, switch, optical transceiver, and server. In general, the bandwidth to describe the analog channel capacity. The data rate to describe the digital channel capacity. (However, in many cases, the term “bandwidth” is also used to describe the capacity of a channel. For example, the bandwidth of a channel is 56kb / s, which means