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单选

有关帧中继和X.25的说法不正确的是(25)。

  • A.X.25强调网内数据传输的高度可靠性,而帧中继则着眼于数据的快速传输,最大程度地提高网络吞吐量
  • B.帧中继省略了X.25的分组层(即网络层),并以链路层的帧为基础对分组层进行层间操作
  • C.帧中继提供了透明的、对每条虚电路都进行的流量控制机制
  • D.X.25网是一个确认型的网络,而帧中继是非确认型的网络
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