计算机网络-第5章 5.3-多路访问链路和协议-同步电大进度

「爱情、让人受尽委屈。」 2023-01-15 05:58 174阅读 0赞

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关于CSMA/CD描述错误的是（）。

*  A.在发送数据帧之前，先侦听信道是否空闲，信道空闲才开始传输；信道忙则随机等待，直到侦听到信道空闲才开始传输
 *  **B.在传输过程中，适配器会一直侦听信道是否有来自其他适配器的能量信号，如果检测到，则仍然继续传输数据帧，再丢弃数据帧**
 *  C.在传输过程中，如果适配器没有侦听到来自其他适配器的能量信号，则说明数据帧传输成功
 *  D.以太网采用的是CSMA/CD协议

### 分析随机访问多路协议的效率 ###

分析pure ALOHA、时隙ALOHA、CSMA/CD的效率，给出推导。

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