问题 问答题


阅读下列说明,回答问题1至问题5,将解答填入对应栏内。
【说明】
某一网络地址块192.168.75.0中有5台主机A、B、C、D和E,它们的IP地址及子网掩码如表4-1所示。
表4-1主机IP地址及子网掩码表

主 机IP 地 址子 网 掩 码
 A192.168.75.18255.255.255.240
 B192.168.75.146255.255.255.240
 C192.168.75.158255.255.255.240
 D192.168.75.161255.255.255.240
 E192.168.75.173255.255.255.240

【问题5】
若在该网络地址块中采用VLAN技术划分子网,何种设备能实现VLAN之间的数据转发

答案

参考答案:

解析:要使用路由器或三层交换机来实现VLAN之间的通信。

[分析]: VLAN,虚拟局域网,是一个逻辑的子网或由定义的成员组成的一个网络段,其中的所有设备都是同一广播域(广播域是一组能相互发送广播报文的节点)的成员,通常是基于交换机的端口号(也可以基于MAC地址而动态设置)。VLAN通过将网络分成小的广播域和子网,更加有效地利用了带宽;由于VLAN间强迫进行了第3层路由选择,因此提供了安全性;VLAN允许第3层路由选择协议智能地决定到达的目的地的最佳路径,可以进行负载均衡,还可以减少网络故障的影响,以实现对故障组件的隔离。 在同一个VLAN中的计算机可以进行通信,而在不同的VLAN中的计算机则无法直接通信。它们通常处于不同的IP网段(或其他网络层协议),同时也处于不同的广播域,需要利用三层交换机或路由器来互联。

完形填空

第二节:完形填空(共20小题;每小题1.5分,满分30分)

阅读下面短文,掌握其大意,然后从36-55各题所给的四个选项(A、B、C和D)中选出最佳选项。

For as long as I can remember, I have been very_36____ at arguing with people. As soon as someone disagrees with me, I get angry because I feel __37__, like the other person is out to show that I am __38__. And for some reason, I hate being wrong! So my __39__ reaction is to get very defensive. I __40__ my voice, and I end up saying something I later __41__. Needless to say, the whole thing ends with me blaming __42__, and the other person feeling alienated(疏远) from me. This bothers me especially because my mother does the exact same thing and I hate __43__.

I have noticed this tendency in me for a long time now, __44__ I have never been able to stop. I did some __45__ management work with a therapist(治疗专家) a while ago, but because I moved and __46__ an advisor at school who can’t see me __47__, I have not been able to continue this important work. They tell you to stop and count to 10, __48__ your breathing, calm yourself down before you __49__. But that’s the whole problem. I could never think of __50__ myself until it was too late! The __51__ things had already come out of my mouth, and I was stuck picking up the pieces.

Right now the __52__ is urgent because my relationships with a wonderful boy is __53__ because of my being afraid of being wrong. He is closing himself off from me because I have hurt him, and __54__ I am no longer attractive as a woman with no confidence in myself and a bad temper. How do I stop ruining my relationships and hating myself? How do I stop __55__ being wrong?

36. A. bad                           B. good              C. hateful                     D. quick

37. A. disappointed          B. excited              C. attacked            D. ashamed

38. A. wrong                       B. foolish                 C. empty-headed    D. right

39. A. unusual               B. immediate       C. following          D. last

40. A. raise                          B. lower                C. keep                 D. change

41. A. remember                  B. regret                C. forget               D. realize

42. A. her                              B. him                  C. me                    D. myself

43. A .it                               B. her                   C. them                 D. us

44. A. so                      B. but                   C. although            D. however

45. A. health                        B. action           C. calmness           D. anger

46. A. headed to                   B. asked for           C. turned to          D. referred to

47. A. regularly                    B. carelessly          C. immediately      D. patiently

48. A. stop                           B. manage             C. keep                 D. control

49. A. say                            B. chat                  C speak                 D. talk

50. A. stopping                    B. managing          C. persuading      D. helping

51. A. hurtful                  B. surprising          C. colorful             D. dangerous

52. A. event                         B. thing                 C. affair                D. problem

53. A. in the way                  B. in the end          C. in danger           D. in the beginning

54. A. no doubt                    B. no problem     C. no wonder         D. no way

55. A. liking                        B. hating           C. finding              D. dealing

解答题