问题 单项选择题

自举协议(BOOTP)是DHCP之前开发的主机配置协议,作为对BOOTP协议的扩充,动态主机配置协议DHCP与BOOTP的主要区别是DHCP具有 (66) 机制。DHCP协议支持的中继代理(Relay Agent)是一种 (67) ,它可以在不同的网段之间传送报文。DHCP具有多种地址分配方案,移动终端(比如笔记本电脑)最适合的分配方案是 (68) 。使用Windows 2000操作系统的DHCP客户机,如果启动时无法与DHCP服务器通信,它将 (69) 。因为DHCP报文是装入 (70) 数据单元中传送的,所以它是不安全的。

(70)处是()

A.TCP

B.UDP

C.IP

D.ARP

答案

参考答案:B

解析:

自举协议(BOOTP)是DHCP之前开发的主机配置协议。DHCP在BOOTP基础上进行了改进并消除了 BOOTP和DHCP作为主机配置服务所具有的特殊限制。RFC951定义了BOOTP。由于BOOTP和DHCP之间的关系,两个协议共向某些定义特征。

BOOTP和DHCP使用几乎相同的消息(由客户机发送)和回复消息(由服务器发送)。任何一种协议中的消息都使用576个字节的单个用户数据报协议(UDP)数据报来封装每个协议消息。

BOOTP和DHCP中继代理程序通常将BOOTP和DHCP消息时为基本相同的消息类型,而不做区分。BOOTP通常为每个客户机提供单个IP地址的固定分配,在BOOTP服务器数据库中永久保留该地址。在WINDOWS2000的系统中,如果作为DHCP客户机找到对应的服务器时,将不使用IP地址,获取的值为:0.0.0.0.X。

完形填空

第二节完形填空(共20小题;每小题1分,满分20分)

请认真阅读下面短文,从短文后各题所给的A、B、C、D四个选项中,选出最佳选项。

I love spending weekends with my grandparents. I felt especially welcome and    36    in Grany’s small kitchen. It was there that we had conversations and Grany always seemed to include a bit of    37    with every recipe she prepared.

I remember one Saturday morning    38   . After breakfast I asked Grany, “What kind of soup are you making today?” “Vegetable beef,” she answered, “And you can help by chopping some carrots and celery.” As I slowly peeled carrots, I    39   , “I’ve got to give an oral work report next week and I’m    40   .”

Grany looked at me and said, “Most people are afraid of    41    speaking. But remember, the only thing you have to fear is fear    42   .”

“But I don’t like standing up in front of everybody.    43    I forget what I’m going to say?”

“Have you prepared    44   ?” asked Grany.

“Well, no. That would be a lot of    45    work.”

“But do you like my soup?” she asked. Soup? I wondered. I thought we were talking about my life.

“I love your soup, Grany.” I said.

“Well, you know, a lot of people don’t    46    homemade soup these days. They say it’s too much trouble. First you have to cook a nice broth(肉汤)and then chop all the vegetables into bite-size pieces.”

“But I don’t    47    a little trouble,” she said. “It adds variety and flavor to my soup and to my life. My soup would be    48    bland(淡而无味的)without the vegetables, and so would my life if it didn’t have the little    49   .”

After pausing she added, “Besides, you have to remember God knows exactly    50    he’s cooking up in your life. You’ve got to trust him with the recipe.” She smiled and then walked to the sink to start washing the dishes.

While I help Grany  51  , I thought as well what she had said. I still had a few days to  52    my oral report.

That Saturday, Grany gave me food for thought as well as a bowl of her homemade soup. Every spoonful of Grany’s masterpiece was    53    with delicious bits of meat and vegetables. As I enjoyed the meal with my grandparents,    54    my problems didn’t seem quite so big any more. I was determined to work on them. Grany had said hard work    55   . Maybe I too could turn a little trouble into something as special as Grany’s homemade soup.

36. A. experienced                B. relaxed                     C. withdrawn                D. tortured

37. A. wisdom                            B. affection                  C. anecdote                   D. fantasy

38. A. as usual                            B. above all                  C. in general                 D. in particular

39. A. wept                          B. suspected                  C. complained               D. mourned

40. A. scared                        B. received                   C. conservative             D. deliberate

41. A. public                        B. private                            C. personal                   D. authentic

42. A. others                        B. itself                        C. audience                   D. judges

43. A. Only if                      B. How come                C. So what                   D. What if

44. A. assessment                 B. regulation                 C. deadline                   D. notes

45. A. absolute                            B. subjective                 C. extra                        D. flexible

46. A. decorate                     B. inspect                            C. make                       D. foresee

47. A. add                           B. mind                        C. expose                     D. appoint

48. A. even                          B. pretty                       C. much                       D. far

49. A. ups and downs            B. part and parcel          C. cats and dogs            D. pros and cons

50. A. how                          B. when                       C. what                        D. where

51. A. eat up                        B. do up                       C. pick up                    D. clean up

52. A. distribute                   B. practice                    C. boycott                    D. decline

53. A. loaded                       B. equipped                  C. reformed                      D. resisted

54. A. therefore                    B. however                   C. somehow                  D. moreover

55. A. left off                      B. kept off                    C. took off                   D. paid off

单项选择题