p-持续CSMA协议下，一个用户在发送之前，先侦听信道，若是空闲，就以概率p发送出去，而以q =1-p的概率推迟到下一帧时。如果下一帧时仍是空闲，便再次以概率p发送而以q推迟到再下一帧时。直到发送成功或另外一用户开始发送时为止。若一开始就侦听到信道忙，它就等到下一帧时，然后再开始上述过程。若发生冲突，这等待一随机时间后重新开始。本实验中取q值为0.5。求的是0.5-持续CSMA。

-p-persistent CSMA agreement, a user before sending the first interception channel, if idle, with probability p sent, and to q = 1-p probability postponed to the next fr a mes. If the next fr a me was still idle, they again sent with probability p and q to further postponed to the next fr a mes. Until this a success or other users at the beginning of this date. If an interception at the start of the busy channel, it will wait till the next fr a mes, and then begin the process. If conflict breaks out, waiting for a random period of time after the re-start. The experiments take q value of 0.5. For the 0.5-sustained CSMA.