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局域网常用的拓扑结构有总线、环形、星形3种,以下关于这3种拓扑结构说法错误的是(18)。

  • A.总线网可靠性高、扩充性能好、通信电缆长度短、成本低,但当网上站点较多时会因数据冲突增多而使效率降低
  • B.环形网控制简单、信道利用率高、通信电缆长度短、对节点接口和传输的要求较低,但存在数据冲突问题
  • C.星形网结构简单、实现容易、信息延迟确定,但通信电缆总长度长、传输媒体不能共享
  • D.选用何种拓扑结构,首先要考虑采用何种媒体访问控制方法,其次要考虑性能、可靠性、成本、扩充性、实现难易以及传输媒体的长度等因素
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