问题 填空题

在共享介质方式的总线型局域网实现技术中,需要利用 __________________方法解决多结点访问 共享总线的冲突问题。

答案

参考答案:CSMA/CD 或者 载波监听多路访问/冲突检测

解析:共享介质访问控制方式主要有三种:带有冲突检测的载波侦听多路访问(CSMA/CD)方法;令牌总 线方法(TOKEN BUS);令牌环方法(TOKEN RING)。其中 CSMA/CD 介质访问控制方法用于总线型局域网解决多结点访问共享总线的冲突问题。

单项选择题
单项选择题

Recently, I flew to Las Vegas to attend a meeting. As we were about to arrive, the pilot announced with apology that there would be a slight (16) before setting down. High desert winds had (17) the airport to close all but one runway. He said that we would be (18) the city for a few minutes waiting to (19) . We were also told to remain in our seats meanwhile with our seat belts fastened (20) there might be a few bumps(颠簸). Well, that few minutes turned into about four-five minutes, including a ride that would make a roller coaster(过山车) (21) by comparison. The movement was so fierce that several passengers felt (22) and had to use airsickness bags. As you might guess, that’ s not a good thing to have happen in a(n) (23) space because it only (24) to increase the discomfort of the situation.

About twenty minutes into the adventure, the entire airplane became very (25) There was now a sense of anxiety and fear that could be (26) noticed. Every passenger simply held on for dear life …except one. A (27) was having a good time! With each bump of the (28) , he would let out a giggle (咯咯地笑)of delight. As I observed this, I (29) that he didn’t know he was supposed to be afraid and worried about his (30) . He neither thought about the past nor about the future. Those are what we gown--ups have learned from (31) . He was (32) the ride because he had not yet been taught to fear it. Having understood this, I took a deep breath and (33) back into my seat, pretending I was (34) on a roller coaster. I smiled for the rest of the flight. I even (35) to giggle once or twice, much to the chagrin(随恼) of the man sitting next to me holding the airsickness bag.

(30)()

A.health

B.safety

C.joy

D.future