Example 12.2 UNI A pure ALOHA network transmits 200-bit frames on a shared channel of 200 kbps.What is the requirement to make this frame collision-free? 一个纯ALOHA帧长200比特，带宽200kbps,这个帧在传输过程中无冲 突的条件是什么？ Solution Average frame transmission time Tfr is 200 bits/200 kbps or I ms. The vulnerable time is 2 X I ms 2 ms.This means no station should send later than I ms before this station starts transmission and no station should start sending during the one 1-ms period that this station is sending. 帧的传输时间为Tr=200bits/200kbps=1ms.则可能的冲突时间 为2ms。意味着前1ms和后1ms都没有其它站发送数据帧。 12.10 12.10 A pure ALOHA network transmits 200-bit frames on a shared channel of 200 kbps. What is the requirement to make this frame collision-free? 一个纯ALOHA帧长200比特，带宽200kbps, 这个帧在传输过程中无冲 突的条件是什么？ Example 12.2 Solution Average frame transmission time Tfr is 200 bits/200 kbps or 1 ms. The vulnerable time is 2 × 1 ms = 2 ms. This means no station should send later than 1 ms before this station starts transmission and no station should start sending during the one 1-ms period that this station is sending. 帧的传输时间为Tfr = 200 bits/200 kbps = 1 ms. 则可能的冲突时间 为2ms。意味着前1ms和后1ms都没有其它站发送数据帧