不属于网桥分割网络所带来好处的是（）。

正确答案：D

参考答案：The further development of economy in China has brought the more entertainment and leisure to people’s life.A case in point is the long holiday such as the National Day, in which people can spend one week or so enjoying themselves in different ways, especially going shopping and traveling.It has been agreed that the long holiday may bring much more benefit to both the customer and the businessmen.
On the other hand, however, the long holiday also brings much expectable problems to the society.First, too many visitors in the long holidays have caused the strain in traffic.Second, the visitors like to go to the well-known interesting places, which may lead to the serious damage to the nature and the scene.
In my view, people need such long holidays, and what really matters is how to guide people in their entertainment.For example, it is advisable that people try to avoid going shopping or traveling in the rush days.Anyway, the long holiday is a good idea of satisfying both the people and the merchants.

正确答案：C
(20)C) 【解析】网桥是在数据链路层上实现不同网络的互联的设备，显然答案选C）。网桥的基本特征为：(1)网桥能够互联两个采用不同数据链路层协议、不同传输介质与传输速度的网络；(2)网桥以接收、存储、地址过滤与转发的方式实现互联的网络之间通信；(3)网桥需要互联的网络在数据链路层以上采用相同的协议；(4)网桥可以分隔两个网络之间的广播通信量，有利于改善互联网络的性能和安全性。由(2)可知A）错误，由(3)可知c) 错误。

正确答案：D

答案：D

解析：

正确答案：D
(23)D) 【解析】网桥的设计有以下几点需要强调：(1)网桥不更改接收帧的数据字段的内容和格式，只简单地将每个要传输的帧从一个局域网中复制下来，再原封不动地传送到另一个局域网，因此它要求两个局域网在MAC 层以上使用相同的协议；(2)衡量网桥性能的参数主要是每秒钟接收与转发的帧数；(3)网桥必须具有寻址能力和路由选择能力；(4)网桥所连接的局域网的MAC层与物理层协议可以不同。故D)的说法是错误的。